Decision Making for Patients with Asymptomatic Severe Aortic

Stenosis

The Case for Preemptive Aortic Valve Replacement Surgery

Tulvio S. Durand

BSEE, Villanova University, Math/Science Teaching Credentials, University of California,

San Diego, Resident of Anza, CA, U.S.A.

Keywords: Asymptomatic, Aortic Stenosis, Aortic Valve Replacement, Decision Making.

Abstract: Aortic stenosis disease typically progresses from mild to severe as patients age beyond 50, during which

time patients are generally asymptomatic and their quality of life will remain similar to that of the general

population. Most patients with Asymptomatic Severe Aortic Stenosis (ASAS) will develop one or more

symptoms of angina, dyspnea, or syncope within five years. As there is no medicinal cure for the disease,

these newly symptomatic patients will require Aortic Valve Replacement (AVR) surgery soon after onset of

symptoms because without it 75% of them will die within three years from the first symptoms onset. The

proper treatment of ASAS patients before they become symptomatic is subject to debate. The American

College of Cardiology and American Heart Association (ACC/AHA) recommend “watchful waiting” for the

onset of symptoms after which they recommend AVR surgery. Review of results of studies based on

recently improved surgical outcomes indicate that preemptive AVR surgery before onset of symptoms

produces vastly improved survivability compared to the watchful-waiting protocol. ACC/AHA guidelines

for treatment of severe aortic stenosis accordingly should be modified to reflect this new reality by

recommending early AVR surgery in place of watchful waiting for most all ASAS patients.

1 INTRODUCTION

The proper treatment of Asymptomatic Severe

Aortic Stenosis (ASAS) patients during the

asymptomatic period is controversial. Though the

cardiologist knows from testing that AVR surgery

will soon be needed, the patient is reluctant to have

surgery because he does not experience symptoms.

The cardiologist is also reluctant to recommend

surgery because of the operative mortality risk

which until recently was substantial. Consequently

the American College of Cardiology and American

Heart Association (ACC/AHA) recommend (in

Bonow, R., Carabello, B., et al. 2006) “watchful

waiting” for the onset of symptoms before

considering Aortic Valve Replacement (AVR). But

if onset of symptoms is not quickly recognized and

acted upon the patient is subject to sudden death, as

is explained in the Section 2 discussion that follows.

Cardiology researchers have been seeking an

indicator or combination of indicators that can

reliably signal when onset of symptoms is imminent

so that early AVR surgery in such patients may be

warranted, especially when very low surgical

mortality risk is expected. Operative mortality risk

in a high volume AVR surgical theater with highly

experienced surgeons is now typically 1% to 2% for

isolated AVR surgery and 3% to 5% for more

complex AVR surgery as reported in Egrie et al.,

(2010) and Stanford SHC (2013). Complex AVR as

used herein involves one or more of: repair and/or

replacement of multiple heart valves, coronary

bypass, or debridement of a heavily calcified aortic

valve, in addition to AVR.

Review of event-free survival data from one

large study presented and discussed in Section 3

indicates astoundingly large 43% mortality is

experienced with those ASAS patients during the

watchful-waiting period of five years. With such

large attrition, the question that comes to mind is

how many of those ASAS patients who died during

watchful waiting would have survived had all them

been given, and all accepted, the option of having

early AVR surgery in today’s expected low

operative mortality risk for this surgical procedure?

S. Durand T..

Decision Making for Patients with Asymptomatic Severe Aortic Stenosis - The Case for Preemptive Aortic Valve Replacement Surgery.

DOI: 10.5220/0004615000490056

In Proceedings of the International Congress on Cardiovascular Technologies (CARDIOTECHNIX-2013), pages 49-56

ISBN: 978-989-8565-78-5

 2013 SCITEPRESS (Science and Technology Publications, Lda.)

Accordingly, the watchful-waiting data from this

and other studies is reanalyzed in Section 3 to yield

predicted survival percentages for both 2% and 5%

operative mortality risk for AVR surgery. Predicted

survival from early AVR surgery is shown to be

vastly superior to survival from watchful waiting.

Moreover, the data from a recent study is very

significant and unique because it directly compares

actual AVR surgery survival to watchful waiting

survival of ASAS patients. The AVR surgery

subgroup of patients experienced significantly

superior survival compared to the subgroup of

patients in watchful waiting. Finally, in two separate

studies of elderly patients, long term survival of

ASAS patients is compared between those who had

AVR surgery with those who were in watchful

waiting and did not have AVR surgery. The long

term survival of patients who underwent AVR

surgery was again vastly superior in both studies.

Moreover their long term survival was also

significantly superior to the survival of the referent

general population when matched for age and

gender.

These results make a strong case for changing

the recommended treatment protocol for ASAS

patients. In other words, the time has come for the

ACC/AHA to reconsider their position on the

treatment of asymptomatic patients with severe or

extremely severe aortic stenosis and recommend

early AVR surgery for most all such patients.

Exceptions might include patients with significant

comorbidities like cancer.

It should be noted throughout this paper that

advocacy for AVR surgery treatment of ASAS

patients applies equally to asymptomatic patients

who have very severe or extremely severe aortic

stenosis. Asymptomatic severe aortic stenosis

(ASAS) and asymptomatic extremely severe aortic

stenosis are defined in Table 1, Section 2.

Asymptomatic very severe aortic stenosis

designation and criteria for its designation may vary

by author. This topic is expanded when treating such

data and is further discussed in Section 3.

2 DISCUSSION

The American College of Cardiology and American

Heart Association (ACC/AHA) have jointly issued

severity-grading criteria of aortic stenosis as well as

provided guidelines for aortic valve replacement

(Bonow, 2006). A succinct restatement of

ACC/AHA’s severity grading of aortic stenosis is

shown in Table 1, and summary restatement of its

guidelines for asymptomatic patients are excerpted

and restated below Table 1. Note also that Table 1

and AVR guidelines are the result of combining

separate data in Bonow et al., (2006 pp. 97, 101, 107

and 120).

Table 1: ACC/AHA grading of aortic stenosis.

EXTREMELY

SEVERE

SEVERE MODERATE MILD

Jet velocity

(m/s)

>5.0 >4.0 3.0-4.0 <3.0

Mean aortic

gradient (mm

Hg)

>60 >40 25-40 <25

Aortic valve

area (cm

)

<0.6 <1.0 1.0-1.5 >1.5

Indexed*

aortic valve

area (cm

)

- <0.6 - -

*indexed to patient’s body surface area



The corresponding ACC/AHA guidelines

from

Bonow et al., (2006) regarding advisability of AVR

in asymptomatic aortic stenosis patients are as

follows:

1. AVR may be considered for asymptomatic

patients with severe aortic stenosis and any of the

following:

- An abnormal response to exercise.

- A high likelihood of rapid progression of aortic

stenosis disease.

- When surgery might be delayed at the time of

symptom onset.

2. AVR may also be considered for asymptomatic

patients with extremely severe aortic stenosis and

when the patient’s expected operative mortality

is 1.0% or less.

The protocol expressed in these guidelines for

treatment of ASAS patients is commonly referred to

in the literature as watchful waiting, in which the

patient is medicinally treated and periodically

monitored or tested for the onset of symptoms. It is

important to note that these ACA/AHA guidelines

from Bonow et al., (2006) are based on older pre

2000 valve-prosthesis technology and AVR surgical

outcomes that have since greatly improved. For

example ACA/AHA guidelines in Bonow et al (2006

p. 108) quotes the average perioperative mortality

values thusly: “3% to 4% for isolated AVR, 8.8%

mortality for AVR in patients over age 65 which can

also reach 13% mortality in low-volume AVR

centers”. These mortality percentages have been at

least halved in recent practice as can be seen, for

example, in Egrie et al., (2010) and Stanford (2013)

CARDIOTECHNIX2013-InternationalCongressonCardiovascularTechnologies

and in the two studies of AVR in the elderly patients

reported in Section 3.3. Moreover ACA/AHA

properly anticipated this progress where they state in

Bonow et al (2006 p. 109) “… as improved valve

substitutes are developed and methods of valve

replacement become safer, the risk-benefit balance

may change to favor earlier intervention in aortic

stenosis”. It appears that the time for favoring and

recommending earlier AVR intervention has arrived.

2.1 The Problem with

Watchful-waiting Protocol

The big problem with watchful-waiting protocol as

deduced from data presented and discussed below is

that a significant percentage of ASAS patients

routinely die from the underlying aortic stenosis

disease during watchful waiting that would have

survived if they had they had undergone early AVR

surgery before the onset of symptoms. The same

logic applies to asymptomatic patients with extreme

aortic stenosis, as they should be recommended for

immediate AVR surgery, asymptomatic or not.

Supporting this position are the results from four

studies described in Section 3 that compare survival

rates from watchful waiting to predicted and actual

results of early AVR. But before delving into the

results of the studies it is important to note that

survivability is reduced from three causes: aortic

stenosis disease, normal aging effects, and mortality

risk associated with AVR surgery. An overview of

survivability versus age and the impact of onset of

aortic stenosis symptoms on survivability are each

illustrated in Figure 1.

Gender-specific survivor curves of the general

population based on 2007 U.S life expectancy data

obtained from the Life Expectancy Calculator

(2013) are depicted in Figure 1. For example, 91.2%

females aged 60 are survived to the present from

the100% of that group when born. The

corresponding percentage survivors for males aged

60 is 85.2%. The studies of Carabello (2012), Shah

(2012), and others agree that ASAS patients have

approximately equal life expectancy as the general

population during the time they remain

asymptomatic. After onset of symptoms the life

expectancy of symptomatic patients with aortic

stenosis nosedives as is illustrated by the two dotted

“no-surgery” lines, with the result that three quarters

of those patients die within three years if they do not

undergo AVR surgery, according to Carabello

(2012) and Shah (2012).



Figure 1: General Population Average Survival versus

Age and Illustrated Effect of Symptoms Onset on Survival

without AVR Surgery. (The “No Surgery” data was

adapted from Shah (2012, Fig.1A, p. 2).

2.2 “Watchful Waiting” Makes the

ASAS Patient a Ticking Time

Bomb

The onset of symptoms has to be detected early and

reported quickly to the monitoring cardiologist. The

penalty for not promptly undergoing AVR surgery

after first onset of symptoms is the loss of 2%

survivability for every month of delay according to

Carabello (2012). Realize that the latter penalty for a

one-month delay equates or exceeds to the 30-day

mortality risk of 1% to 2% for isolated AVR

surgery, the latter is based on operative mortality

risk data of Egrie et al., (2010) and others. Early

detection and prompt reporting of the onset of

symptoms is not only vitally important, it is also

difficult to achieve outside the clinically controlled

environment of hospital or health clinic for various

reasons, including those reasons described in 2.2.1 -

2.2.4.

2.2.1 Onset of Symptoms is often Masked

Recalling that ASAS patients enjoy the same quality

of life as the general population while they are

asymptomatic, there is a natural tendency for them

to deny the existence and seriousness of symptoms

once they do occur. Bonow (2006, p. 103) adds “It

is important to emphasize that symptoms may be

subtle and often are not elicited by the physician in

taking a routine clinical history”.

2.2.2 Sedentary and Low-aerobic Demand

Sports and Routine Yard Work do not

Produce Symptoms

A physically inactive ASAS patient will frequently

not recognize the onset of symptoms because of lack

100

40 60 70 80 90 100

%SURVIVORS

AGE

Male

Female

No

Surgery

Symptoms

Onset

Fig. 2

DecisionMakingforPatientswithAsymptomaticSevereAorticStenosis-TheCaseforPreemptiveAorticValve

ReplacementSurgery

of the type of exercise that would unequivocally

bring on the symptom; example activities that don’t

produce symptoms are card playing, watching TV,

and watering the roses. Also, golfing from a golf cart

is generally not sufficiently aerobic to bring about

symptoms of progressing aortic stenosis disease.

2.2.3 Advancing Age and Medications often

Produce Similar Symptoms

Dyspnea symptoms of extreme shortness of breath,

tiredness and feelings of exhaustion following

exercise are often and incorrectly attributed to

advancing age. Angina can sometimes be confused

with expected muscular soreness from repetitive

types of yard work. Syncope can be confused with

expected side effects of medications being taken for

hypertension and other health problems.

2.2.4 Physical Intensity and Performance

Level in Sports and Work are often

Lowered in the Face of

Symptom-related Declining

Capabilities

A tennis player, for example, will often opt to make

the games and points shorter when he becomes

extremely tired and may play less often to mask a

loss of vigor from what the player thinks are simply

the vagaries of advancing age. This same adaptive

behavior can also mask the real onset of symptoms

of aortic stenosis disease.

Clearly there is a need for educating all aortic

stenosis patients on what to watch for and to

immediately report suspected onset of symptoms.

“Valve Clinics” should be established at hospitals

where aortic stenosis patients can be educated and

more closely monitored during watchful waiting.

Exercise stress tests should be periodically

employed for all ASAS patients in clinical settings

to see if they produce symptoms. The stress test is

often intentionally avoided by cardiologists for fear,

mostly unsupported, that it can bring on heart

failure, and is of itself yet another reason that

symptoms are sometimes not recognized early

enough to keep mortality rates low. Suffice it to say

that watchful waiting for onset of symptoms is a

dangerous protocol for ASAS patients. It will be

shown herein that a much safer alternative to

watchful waiting is early AVR surgery. But it is to

be expected that watchful-waiting protocol will not

be abandoned anytime soon, so care must be

exercised to make it work as well as possible.

2.3 The AVR Surgery Option

There are two categories of AVR cardiac surgery

considered herein: Isolated AVR surgery and more

involved or what is referred in this paper as complex

AVR surgery. Isolated AVR surgery involves the

removal and replacement of the aortic valve only

and is usually performed using minimally invasive

surgery techniques. The 30-day expected mortality

risk from Isolated AVR is 1% to 2% as

demonstrated in Egrie (2010), Stanford (2013),

Kang (2010) and Varadajaran (2006), and depends

on the experience of the surgical team and AVR

surgery volume of the hospital; the more

conservative 2% is used herein in survivability

calculations for Isolated AVR surgery. Complex

AVR surgery can involve surgical repair and/or

replacement of multiple heart valves, coronary

bypass, debridement of a heavily calcified aortic

valve, and a host of other cardiovascular surgical

procedures in addition to AVR. The 30-day expected

mortality from complex AVR is 3% to 5%

also as

demonstrated in Egrie et al., (2010) and Stanford

(2013) depending on the experience of surgical team

and AVR volume of the hospital; the more

conservative 5% is used in survivability calculations

herein. As a point of interest, Isolated AVRs

constituted about one-half of the 2532 total AVRs

performed by one surgical group during the 11 year

period 1998-2008 as reported in Egrie (2010, p. 16).

Survivability from the Isolated AVR surgery

option with 30-day 2% mortality risk is illustrated in

Figure 2.

Note that all calculations that follow are

based on male life expectancy only, which is the

more conservative choice since male life expectancy

is shorter.

A portion of the General Population Survivors

(solid black line) is replicated from the small

rectangular area in Figure 1 spanning the ages 74.5

years to 76.5 years. That line shows the expected

decline of the male general population survivors

from aging factors alone based on Life Expectancy

Calculator (2013). At age 75, for example, 61.6% of

all males are survived, and at age 76 the male

survivors reduces to 59.2% in nearly linear fashion.

Assume, for the following discussion, that a

group of 100 ASAS male patients all aged 75 opt to

have Isolated AVR surgery for which the expected

30-day operative mortality risk is 2%. Those

patients’ 2% mortality risk is comprised of 1.67%

mortality risk from surgery (line pointed down) and

0.33% mortality risk from normal aging effects on

the general population during the 30-day

postoperative period (shown by very short line

CARDIOTECHNIX2013-InternationalCongressonCardiovascularTechnologies

segment parallel to the general population aging

line). Of the initial 100 ASAS patients, two of them

do not survive AVR surgery (dotted arrow facing

down towards 0%). The remaining 98 are all

survivors (arrow pointed up), and they rejoin the

general population group in life expectancy (parallel

lines shown for clarity only). Importantly, the AVR

surgery survivors can expect at least the same, and

possibly greater life expectancy compared to that of

the general population as is reported in the two AVR

survival studies in Section 3.3.

The more complex AVR surgery with 30-day

mortality risk of 5% is similarly represented by

Figure 2, except the mortality dip would be 3%

larger. But the 95% surgery survivors are also

expected to attain equal or better life expectancy

compared to the general population as is discussed

in Section 3.

2.4 The ASAS Patient Asks: Which is

Less Risky, Watchful Waiting or

Early AVR Surgery?

At a minimum, the informed views of the patient

should be considered along with those of the

cardiologist and cardiothoracic surgeon.

Accordingly, the ASAS patient should be informed

that he has two options: (1) watchful waiting for

symptoms, after which his/her survival percentage

decreases by 2% per month

according to Carabello

(2012), or (2) Isolated AVR surgery for which there

is a 30-day mortality risk of 2%. Also the patient

should be informed it is not unreasonable to expect

that it could take up to three months or so from

actual symptoms onset (as opposed to delayed

recognition of symptoms onset) to the time of being

wheeled into the operating room for AVR surgery,

so that option (1) could incur up to three times more

mortality risk compared to option (2).

It should also be noted that the Isolated AVR

operative mortality risk 2% could equate to only a

fraction of the yearly mortality risk from aging. For

example the general-population male on his 75

birthday has a 4% probability of dying before age

76. Isolated AVR surgery adds only 1.67% mortality

risk which is equivalent to 6 months’ (or 4.7%) loss

in life expectancy. However, to a 40 year male the

2% operative mortality risk equates to about 6.72

years (or 18%) loss of life expectancy, and is

therefore a decision that should not be taken lightly.

Isolated AVR operative mortality risk of < 1%

remains a highly desirable goal especially for

younger, < 55-year patients.

3 STUDIES COMPARING

WATCHFUL WAITING TO

AVR SURGERY

The principal source of survival data from watchful-

waiting protocol treatment of asymptomatic patients

with aortic stenosis disease comes from eight studies

that are aggregated in Bonow et al., (2006, p.104).

Of those only the Pellikka et al., (2005) study is

examined herein because of its being the largest,

comprising over ½ of the total patients, all of whom

were asymptomatic with severe aortic stenosis

disease, and it alone provides results in sufficient

detail relating to the issue of relative efficacy of

watchful waiting protocol compared to early AVR

surgery.

3.1 Pellikka et al., (2005) Watchful

Waiting Study

622 ASAS patients, average age 72 years, Vmax ≥

4.0 m/s, were followed up for a period of five years.

The patients were reevaluated at intervals of six

months or one year and they were told to report

promptly for reevaluation at onset of symptoms.

Those with verified symptoms were recommended

for AVR surgery. A summary of results pertinent to

the present study is shown in Figure 3. Of particular

interest is that by the end of the five-year study

period 265 (43%) patients died and 357 (57%)

patients survived; also of the 352 patients who did

undergo AVR surgery 86 (24%) died.

If at the beginning of the study all 622 patients

had available to them and all opted for AVR, with

either the 2% operative risk for Isolated AVR

surgery or the 5% operative mortality risk associated

with complex AVR (defined in Section 2.3), their

predicted 5-year survival rates would have been 81%

and 78% respectively. These are both markedly

superior to the 57% survival rate actually

experienced. Far fewer patients would have died:

118 for Isolated AVR and 134 for complex AVR,

fatality numbers that are about one-half the 265 total

deaths experienced. Yet, these results are not too

surprising when considering that the results of the

Pellikka (2005) retrospective study represent 24

year-old (1984-1995) AVR surgical and valve

prosthesis technologies. Also as noted above, the

mortality rate for those who elected to undergo AVR

surgery was an abysmally large 24%. It is not

surprising then that, as shown in Figure 3, 90

patients (30%) opted not to have AVR surgery even

after their having developed deadly symptoms.

DecisionMakingforPatientswithAsymptomaticSevereAorticStenosis-TheCaseforPreemptiveAorticValve

ReplacementSurgery

Figure 2: Illustration of Isolated AVR Surgical Option with 30-Day 2% Operative Mortality for a Group of 100 Male

Patients All Aged 75 years.



Figure 3: Distribution of Patients Who Developed Symptoms, Did Not Develop Symptoms, Underwent AVR Surgery,

Survived or Died over the Five Year Study Period; from Pellikka et al., (2005, p. 4, Figure 2 with modified wording).

Pellikka et al., (2005, p. 6) similarly sensed this

reality by stating “Early referral to aortic valve

surgery, even in the asymptomatic patient, probably

would have improved survival”.

3.2 Kang et al., (2010) Study Comparing

Early AVR Actual Surgery Survival to

Watchful Waiting Survival

A noteworthy recent study by Kang et al., (2010)

uniquely compares early AVR actual surgery results

58,0

58,5

59,0

59,5

60,0

60,5

61,0

61,5

62,0

74,6 74,8 74,10 75,0 75,2 75,4 75,6 75,8 75,10 76,0 76,2 76,4 76,6

%SURVIVORS

AGE[Yr,Mo's]

The2%Surgery‐

Non‐survivors

General

Population

% Survivors

Surgery‐

OptingASAS

Patients

The98%

Surgery

Survivor

30‐Day

Aging

Mortality

died

162

survived

died

survived

died

104

survived

103

died

survived

622PATI ENTS

297develop

symptoms

325re ma i n

asymptomatic

207have

surgery

90no

surgery

145have

surgery

180no

surgery

CARDIOTECHNIX2013-InternationalCongressonCardiovascularTechnologies

against conventional treatment (watchful waiting)

results in a group of 197 asymptomatic very severe

aortic stenosis patients. That group was split into

two subgroups, one slated for early AVR surgery

and the other subgroup for traditional watchful

waiting. Very severe aortic stenosis is defined by the

authors as “a critical stenosis in the aortic valve,

area ≤ 0.75 cm

, accompanied by either a peak

aortic jet velocity ≥ 4.5 m/s or a mean transaortic

pressure gradient ≥ 50 mm Hg. There were no

significant differences between the two subgroups in

terms of age, gender, or LV ejection fraction”. AVR

surgery was performed on 102 patients and

conventional treatment [ed. watchful waiting] was

employed for the other group of 95 patients whose

mean age was 63.

The authors (Kang et al., 2010, p. 1, Abstract)

state “During a median follow-up of 1501 days the

operated group had no operative mortalities, no

cardiac deaths, and 3 non-cardiac deaths; the

conventional treatment [ed. watchful waiting] group

had 18 cardiac deaths and 10 non-cardiac deaths”.

Admittedly this is a small study, but the results

nevertheless are very compelling. Early, or

preemptive, AVR surgery won hands down

compared to watchful waiting. Additional

comparative experimental studies to validate these

results are recommended.

3.3 Two Studies of Elderly Patients

with Severe Aortic Stenosis

Comparing their Long-term

Survival from AVR Surgery to

No-AVR (Watchful Waiting) and to

a Control Group

These are two important studies for two reasons:

(1) They directly compare the long term survival of

(A) Severe Aortic Stenosis (SAS) patients who

underwent AVR surgery to (B) SAS patients in

watchful waiting who did not have AVR surgery,

and to (C) control group of U.S. general population

that is matched for age and gender.

(2) Elderly patients with severe aortic stenosis are

often denied AVR surgery because of their advanced

age. Both studies’ results, shown below, strongly

refute the advanced-age argument.

The respective results of the two studies, by

Varadajaran and Kapoor, (2006) and Egrie and

Gaudiani, (2010) are shown in Table 2.

Table 2: Elderly SAS patients’ long-term survival

comparison with AVR, No-AVR, and control group.

Varadajaran, et al.,

(2006)

1 year 2 year 5 year

US GP 85 year Male 89% 79% 50%

AVR Group (n = 55) 87% 78% 68%

No-AVR (n= 222) 52% 40% 22%

Egrie et al., (2010) 1 year 2 year 5 year

US Age and Gender

Matched, ≥ 75 years

89% 79% 51%

Isolated-AVR (n = 371) 91% 87% 67%

No-AVR Group (n = ?) 65% 41% 8%

3.3.1 Varadajaran et al., (2006) Elderly

ASAS Patients, Aged 85 ± 4 Years,

AVR Long-term Survival Study

277 ASAS patients, 85 ± 4 years had aortic valve

area < 0.84 cm

in this retrospective study. The 1, 2,

and 5 year survival percentages of the AVR group

are vastly superior to the No-AVR group, and the 5-

year survival of the AVR group is also significantly

superior to the reference US general population 85-

year male expected survival per the U.S. Life

Expectancy Calculator (2013).

3.3.2 Egrie et al., (2010) Elderly, Age > 75

Years, Isolated-AVR Surgery

Long-term Survival Study

371 aortic stenosis patients aged 75 and over

underwent Isolated AVR surgery from 2004 to 2008

and were followed through 5 years after surgery.

Importantly, it should be noted that all 371 patients

were screened to be free of coronary disease or

cancer, otherwise they would not have been selected

for Isolated AVR surgery. The 1, 2, and 5 year

survival percentages of the Isolated-AVR surgery

group are greatly superior to corresponding

percentage survivors in the No-AVR group.

Moreover, the 2 and 5 year Isolated-AVR survival

percentages also are significantly superior to the age

and gender matched U.S. general population.

4 CONCLUSIONS

1. Predicted and actual survival from preemptive

early AVR surgery with either 2% or 5% operative

mortality risk are shown to be overwhelmingly

superior compared to watchful-waiting protocol in

studies of 717 asymptomatic severe aortic Stenosis

(ASAS) patients.

DecisionMakingforPatientswithAsymptomaticSevereAorticStenosis-TheCaseforPreemptiveAorticValve

ReplacementSurgery

2. Actual long-term survival of 426 elderly, 75-90

year old patients with severe aortic stenosis who

underwent AVR surgery is vastly superior to

survival of those similarly afflicted patients without

AVR surgery; and their survival rates are also

significantly superior to expected survival of age and

gender-adjusted general population control group.

3. ACC/AHA 2006 Guidelines

in Bonow (2006) for

management of aortic stenosis disease should be

revised to recommend preemptive early AVR

surgery when aortic stenosis disease has progressed

to their defined “severe” level regardless of whether

the patient is symptomatic or asymptomatic.

4. Mortality risk from just a single month of

watchful waiting after onset of aortic stenosis

symptoms equates or exceeds the 30-day 1% to 2%

operative mortality risk from Isolated AVR surgery.

5. Onset of symptoms from aortic stenosis disease

is often masked causing delayed detection. Also,

symptoms are sometimes mistaken for benign

effects of ageing, and are sometimes not promptly

communicated to the monitoring cardiologist. Such

delays increase mortality risk by 2% per month, one

month of which equates or exceeds the 1% to 2%

operative mortality risk of Isolated AVR surgery.

6. ASAS patients should be thoroughly apprised of

the vastly superior probable survival from early

AVR surgery compared to the more risky watchful-

waiting protocol. Moreover, advanced age should,

by itself, never be reason to preclude AVR surgery.

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CARDIOTECHNIX2013-InternationalCongressonCardiovascularTechnologies