Aortic valve replacement with and without coronary artery bypass surgery

Angina in patients with severe aortic stenosis undergoing transcatheter aortic valve replacement

INTRODUCTION AND OBJECTIVES

To evaluate the prevalence, clinical characteristics, and outcomes of patients with angina undergoing transcatheter aortic valve replacement (TAVR) for severe aortic stenosis.

METHODS

A total of 1687 consecutive patients with severe aortic stenosis undergoing TAVR at our center were included and classified according to patient-reported angina symptoms prior to the TAVR procedure. Baseline, procedural and follow-up data were collected in a dedicated database.

RESULTS

A total of 497 patients (29%) had angina prior to the TAVR procedure. Patients with angina at baseline showed a worse New York Heart Association (NYHA) functional class (NYHA class> II: 69% vs 63%; P=.017), a higher rate of coronary artery disease (74% vs 56%; P <.001), and a lower rate of complete revascularization (70% vs 79%; P <.001). Angina at baseline had no impact on all-cause mortality (HR, 1.02; 95%CI, 0.71-1.48; P=.898) and cardiovascular mortality (HR, 1.2; 95%CI, 0.69-2.11; P=.517) at 1 year. However, persistent angina at 30 days post-TAVR was associated with increased all-cause mortality (HR, 4.86; 95%CI, 1.71-13.8; P=.003) and cardiovascular mortality (HR, 20.7; 95%CI, 3.50-122.6; P=.001) at 1-year follow-up.

CONCLUSIONS

More than one-fourth of patients with severe aortic stenosis undergoing TAVR had angina prior to the procedure. Angina at baseline did not appear to be a sign of a more advanced valvular disease and had no prognostic impact; however, persistent angina at 30 days post-TAVR was associated with worse clinical outcomes.

Outcomes after aortic valve replacement for aortic valve stenosis, with or without concomitant coronary artery bypass grafting

OBJECTIVES

To assess the effects of concomitant coronary artery bypass grafting (CABG), we analyzed the outcomes after aortic valve replacement (AVR) for aortic stenosis (AS) with and without coronary artery bypass grafting (CABG) at our institution.

METHODS

Between 2002 and 2014, 605 consecutive patients underwent AVR for AS. Of these, the 275 who received isolated AVR (Group A) and the 122 who received both AVR and CABG (Group AC) patients were enrolled, after the exclusion of 8 patients who underwent reoperation and 200 who received other concomitant surgery. AVR and all bypass anastomoses were performed under intermittent retrograde cold blood cardioplegia. Multivariate analysis was used to assess any association of concomitant CABG with morbidity and mortality. Kaplan-Meier analysis was used to assess all-cause mortality.

RESULTS

No significant difference in 30-day mortality was found between Group A and Group AC (1.5% vs. 0.8%, P = 1.000). Nor did post-discharge survival differ significantly between the two groups (P = 0.20). Likewise, multivariate analysis showed that concomitant CABG was not associated with significantly greater in-hospital or mid-term mortality. Operative morbidities were comparable between the two groups, in terms of stroke (1.8% vs. 3.3%, P = 0.466), prolonged ventilation (4.0% vs. 5.5%, P = 0.565), deep sternal infection (1.8% vs. 3.3%, P = 0.466), and acute renal failure (0.4% vs. 1.6% P = 0.176).

CONCLUSIONS

Concomitant CABG at the time of AVR was performed without increasing early- or mid-term mortality. This absence of increased risk deserves consideration when choosing between different treatment strategies.

The prognostic impact of concomitant coronary artery bypass grafting during aortic valve surgery: implications for revascularization in the transcatheter era

OBJECTIVE

Clinicians may give greater consideration to medical management versus coronary artery bypass grafting (CABG) for coronary artery disease (CAD) at the time of aortic valve intervention. We evaluated the prognostic impact of revascularization strategy during aortic valve replacement (AVR).

METHODS

We studied 1308 consecutive patients with significant CAD (≥50% stenosis) undergoing AVR with or with out CABG between 2001 and 2010. Late mortality and its determinants were analyzed using multivariable Cox models.

RESULTS

Patients undergoing CABG (n = 1043; 18%) had more frequent angina (50% vs 26%; P < .001), left ventricular dysfunction (22% vs 14%; P = .003), advanced (>70% stenosis) CAD (85% vs 48%; P < .001), and incidence of triple-vessel/left-main CAD (44% vs 8%; P < .001). Whereas operative mortality was comparable between patients undergoing AVR plus CABG versus isolated AVR (2.9% vs 3.0%; P = .90), 5-year (72% vs 64%) and 8-year (50% vs 39%) survival was higher following CABG (P = .007). Adjusting for older age (hazard ratio [HR], 1.28 per 5 years), female sex (HR, 1.23), peripheral vascular disease (HR, 1.71), New York Heart Association functional class III to IV (HR, 1.48), and diabetes (HR, 1.50) concomitant CABG at AVR reduced late mortality risk by more than one-third (HR, 0.62, 95% confidence interval, 0.49-0.79; P < .001). CABG continued to confer a survival advantage in patients with moderate (50%-70%) (HR, 0.62; P = .02) and severe (>70%) CAD (HR, 0.62; P = .002).

CONCLUSIONS

In patients undergoing AVR with coexistent CAD, concomitant CABG reduces risk of late death by more than one-third, without augmenting operative mortality. This survival advantage persists in moderate (50% to 70%) and severe (>70%) CAD. These findings underline the prognostic importance of revascularization in this population and should influence decisions regarding revascularization strategy in patients undergoing transcatheter valve therapy.

Prevalence of coronary artery disease in patients with valvular heart disease

To evaluate the usefulness of preoperatie coronary angiography in patients undergoing preoperative investigation because of valvular heart disease, we performed coronary angiography in a consecutive series of 329 patients. The prevalence of significant coronary artery disease was 32%. Asymptomatic coronary artery disease was present in 13%. Angina pectoris proved to be a poor predictor of coronary artery disease in aortic valve disease. In mitral valve disease, however, the specificity was high. A cost-benefit calculation was carried out in order to assess what advantage routine coronary angiography might have. According to this, coronary angiography should be performed in all patients suffering from valvular heart disease with angina pectoris, whereas it can be omitted in younger patients without angina. A cut-off point of 60 years seems appropriate for aortic valve disease and 65 years for mitral valve disease.

Aortic valve replacement with combined myocardial revascularisation

Early and late outcome was studied in 630 patients who underwent aortic valve replacement between 1974 and 1982. Group 1 (506 patients) did not have important coronary artery disease, group 2 (69 patients) had coronary artery disease and underwent coronary artery bypass grafting, and group 3 (55 patients) had coronary artery disease but did not undergo myocardial revascularisation. Early mortality (within 30 days of operation) was significantly lower for group 1 (6%) than for group 2 (13%) and for group 3 (16%). Operative mortality in all three groups was lower in patients operated on more recently. The three year survival of patients in group 1 (83%) was significantly higher than that of patients in group 3 (62%) but not than that of patients in group 2 (76%). The findings of this study suggest that the presence of coronary artery disease increases the risk of aortic valve replacement whether or not coronary artery grafting is performed. Myocardial revascularisation, however, seems to return patients with aortic valve and coronary artery disease to a survival curve similar to that of patients with isolated aortic valve disease.

Clinical, hemodynamic, and operative descriptors affecting outcome of aortic valve replacement in elderly versus young patients

One hundred and fifty-two patients age 70 years or more underwent aortic valve replacement (AVR) at Emory University Hospital between July 1, 1974 and July 1, 1982. Of these, 98 had isolated AVR (elderly AVR group) and 54 had concomitant coronary artery bypass grafts (elderly AVR/CABG group). Results of surgery in these patients were compared to results in patients aged 20 to 69 years operated on in the same period (young AVR/CABG groups). Comparative descriptors with statistically significant differences included a higher incidence of both stable and unstable angina in patients undergoing concomitant CABGs ; less cardiomegaly in the young AVR/CABG group; less hypertension, a higher incidence of pure aortic regurgitation, and less frequent use of inotropes in the young AVR group; a higher perioperative stroke rate in elderly AVR/CABG patients; a higher perioperative psychosis rate in patients having CABGs regardless of age; and a longer postoperative hospital stay for the elderly patients. There were no significant differences between the four groups for the following descriptors: sex ratio; history of congestive heart failure; the presence of atrial fibrillation; left ventricular end diastolic pressure, ejection fraction and contractility; number of diseased coronary arteries; number of vessels bypassed; use of the intra-aortic balloon pump; re-exploration for hemorrhage; perioperative myocardial infarction rate; and major wound infection rate. Operative mortality was 5.1% for the elderly AVR group, 5.6% for the elderly AVR/CABG group, 1.9% for the young AVR group, and 5.1% for the young AVR/CABG group (p = NS). Overall, hospital mortality was 3.3%. Actuarial survival curves for all elderly versus all young patients showed no significant difference. The curve for elderly patients compares favorably with the actuarial survival of the same age group in the general population. Actuarial survival curves for the four subgroups did not differ significantly when compared at a follow-up of 36 months after surgery. We conclude that AVR with or without concomitant CABGs can be performed in elderly patients with an acceptably low mortality and morbidity, and the postoperative survival compared favorably both with younger patients and with the general population of the same age.

Prevalence of coronary artery disease in patients with isolated aortic valve stenosis

The prevalence of significant coronary artery disease (reduction in luminal diameter by more than 50%) among 88 consecutive patients with aortic stenosis requiring aortic valve replacement at Hammersmith Hospital was examined. Twenty two (34%) patients had significant coronary disease. Nineteen of 42 (45%) patients with typical angina had coronary disease; three of 20 (15%) patients with atypical chest pain had coronary disease, while none of 26 patients free of chest pain had significant coronary disease. Risk factors for coronary disease were equally distributed among patients with and without significant luminal obstruction. Because of the small, but definite, hazard of coronary arteriography and in the interest of cost containment it is suggested that patients with aortic stenosis who are free of chest pain do not require routine coronary arteriography. This applies particularly to patients requiring urgent aortic valve replacement.

Replacement of aortic valve combined with myocardial revascularization: determinants of early and late risk for 500 patients, 1967-1981

Five hundred consecutive patients underwent aortic valve replacement and coronary revascularization in the years from 1967 to 1981, with 29 (5.9%) in-hospital deaths. Current operative mortality (1978-1981) is 3.4%. Univariate and multivariate analyses were used to identify determinants of early and late risk. Female sex, aortic insufficiency, and advanced age increased in-hospital mortality, whereas use of cardioplegia decreased it. At follow-up of 471 patients who survived hospitalization for 1 to 135 months (mean 41) after surgery, 96 late deaths were documented. Survival rates were 87%, 80%, and 55%, and event-free survival rates were 80%, 65%, and 39% at 2, 5, and 10 years after surgery, respectively. The late survival rate was unfavorably influenced by the presence of moderately or severely impaired left ventricular function and double-vessel coronary disease; the rate was enhanced for patients in age group from 50 to 59 years old and was not influenced by the method of myocardial protection. The event-free survival rate decreased with the presence of moderately or severely impaired left ventricular function and was enhanced for patients with New York Heart Association class I or II symptoms before surgery. Patients with bioprostheses who did not receive anticoagulants had higher survival and event-free survival rates than did either patients with bioprostheses who received anticoagulants or patients with mechanical valves, whether they received anticoagulants or not.

Aortic valve replacement in patients with poor ventricular function-early and late results with long-term follow-up

A series of 62 consecutive patients with an ejection fraction of 0.4 or less (mean 0.28 with a range from 0.10 to 0.40; 22 between 0.10 and 0.20, 18 between 0.21 and 0.30, and 22 between 0.31 and 0.40) who underwent aortic valve replacement from January 18, 1972 to December 20, 1976 was reviewed. Preoperatively two patients were in Class II, 35 in Class III and 25 in Class IV of the New York Heart Association functional classification (N.Y.H.A.). Thirty-nine patients (Group 1) underwent isolated aortic valve replacement and 23 patients (Group 2) underwent aortic valve replacement with associated procedures including aortocoronary bypass in 15. The operative mortality was 8 percent in Group 1, 17 percent in Group 2, and 11 percent overall. In the group of 15 patients with coronary artery disease, the operative mortality of aortic valve replacement and aorto-coronary bypass was 27 percent. Since January 1974, isolated aortic valve replacement was performed with no operative deaths in 25 consecutive patients in Group 1 including 10 patients with an ejection fraction of 0.2 or less. Five-year survival rates were 70 percent in Group 1, 64 percent in Group 2 and 68 percent overall. In the 38 currently living patients, 32 showed clinical improvement and 27 are in Class I or II of N.Y.H.A. In conclusion, isolated aortic valve replacement can be performed with a low mortality and a high survival rate in patients with impaired left ventricular function.

Aortic valve replacement without myocardial revascularization in patients with combined aortic valvular and coronary artery disease

To test the hypothesis that coronary artery bypass grafting (CABG) is not routinely required in patients undergoing aortic valve replacement (AVR) who have coexistent coronary artery disease (CAD), we compared the results of operation in 55 consecutive symptomatic patients who had CAD and underwent AVR without CABG with results in another 142 patients without CAD who underwent AVR during the same period, and with published results from other centers in which CABG was used in patients with CAD who underwent AVR. Operative mortality was 4% in patients with CAD and 5% in patients without CAD. Late survival was not significantly different between the two groups when analyzed for the entire population (80% survival at 3 years in CAD patients, 82% for non-CAD patients), or for the subgroup of patients with aortic stenosis, aortic regurgitation or aortic stenosis plus regurgitation. Eight patients with CAD (15%) developed recurrent angina after AVR (mean follow-up 43 months); only three patients (6%) required CABG because of medically refractory angina (12-43 months). Operative mortality, operative infarction (9%), recurrent angina and long-term survival in patients with CAD after AVR were similar to those at other centers after AVR plus CABG. These data suggest that preoperative detection of CAD does not necessitate CABG in all patients at the time of AVR.

Incidence of coronary artery disease in patients with valvular heart disease

The case notes, cardiac catheterisation data, and coronary arteriograms of 239 patients investigated for valvular heart disease during a five year period were reviewed. Angina present in 13 of 95 patients with isolated mitral valve disease, 43 of 90 patients with isolated aortic valve disease, and 18 of 54 patients with combined mitral and aortic valve disease. Significant coronary artery disease was present in 85 per cent of patients with mitral valve disease and angina, but in only 33 per cent of patients with aortic valve disease and angina. Patients with no chest pain still had a high incidence of coronary artery disease, significant coronary obstruction being present in 22 per cent with mitral valve disease, 22 per cent with aortic valve disease, and 11 per cent with combine mitral and aortic valve disease. Several possible clinical markers of coronary artery disease were examined but none was found to be of practical help. There was, however, a significant inverse relation between severity of coronary artery disease and severity of valve disease in patients with aortic valve disease. Asymptomatic coronary artery disease is not uncommon in patients with valvular heart disease and if it is policy to perform coronary artery bypass grafting in such patients, routine coronary arteriography must be part of the preoperative investigation.

The importance of myocardial protection in combined aortic valve replacement and myocardial revascularization

To determine the importance of different methods of myocardial protection for combined aortic valve replacement and coronary revascularization, we analyzed the records of 82 consecutive patients who underwent the combined procedure between 1973 and 1978. Sixty-three (77%) had angina and 63 (77%) were in New York Heart Association Functional Class III or IV. Moderate to severe left ventricular impairment was present in 59%, and the mean number of diseased vessels was 1.9 per patient. Group I consisted of 18 patients with intermittent ischemia, almost all of whom had operation between 1973 and 1976. Group IIa consisted of 24 patients operated on between 1973 and December, 1976, with coronary perfusion, and Group IIb had 18 patients in whom a similar technique was used in 1977 and 1978. Group III consisted of 22 patients operated on in 1977 and 1978 in whom cold chemical cardioplegia was used. The early mortality (less than 30 days) for Group I was 50% and for Group IIa 29%. There were no deaths in Group IIb and Group III. The incidence of perioperative myocardial infarction was 21% in Group I, 6% in Group IIa, 11% in Group IIb, and zero in Group III. The incidence of cardiogenic shock requiring prolonged inotropic support and intraaortic balloon counterpulsation was significantly less in Group III (9%) than in Group IIb (50%) (p less than 0.05). If other manifestations of myocardial injury, such as perioperative infarction and cardiogenic shock requiring intraaortic balloon counterpulsation or inotropic support, are taken into consideration, cold chemical cardioplegia appears to provide better myocardial protection than coronary perfusion of the fibrillating heart.

Influence of preoperative left ventricular function on results of homograft replacement of the aortic valve for aortic stenosis

The effect of preoperative left ventricular function on early and late prognosis was assessed in 103 patients with aortic stenosis who underwent left ventricular cineangiography before homograft replacement of the aortic valve. The patients were separated into two groups: Group A (58 patients) with an ejection fraction of 0.46 or more and Group B (45 patients) with an ejection fraction of 0.45 or less. The two groups were compared with respect to clinical and hemodynamic data as well as operative result. There was poor correlation between clinical data and left ventricular function. In Group A there were three early deaths (5.2 percent) and three late deaths (5.2 percent) compared with no early and six late deaths (13.3 percent) in Group B during the follow-up period of 12 to 102 months (mean 43 months). Most patients in Group B showed considerable symptomatic improvement but less than that observed in Group A. Forty-two patients (13 in Group A and 29 in Group B) underwent repeat cardiac catheterization and coronary angiography. Improvement in left ventricular function as assessed by radial analysis of segmental wall motion and ejection fraction was observed in 20 of the 29 patients in Group B. Failure of left ventricular function to improve was associated with additional coronary artery disease in the majority of patients. It is concluded that poor left ventricular function does not increase the risk of aortic valve replacement for aortic stenosis and that improvement in left ventricular function can be expected in the majority of patients.

Angina, aortic stenosis and coronary heart disease

The pre-operative clinical and haemodynamic findings of 139 consecutive patients with aortic stenosis were analysed in an attempt to determine the incidence and influence of coronary heart disease on the mode of presentation of patients with aortic stenosis. The overall incidence of coronary heart disease was 32%. 105 patients (76%) presented with angina and of these, 41 patients (39%) had significant coronary heart disease as compared to 4 (13%) of the remaining 34 patients who did not present with angina. Clinical parameters including age, sex, severity of angina together with the presence of associated symptoms and precipitating factors were unhelpful in distinguishing those patients with coronary heart disease. Evidence of previous transmural myocardial infarction or the presence of ST-T abnormalities in the absence of digitalis and the changes of left ventricular hypertrophy were reliable electrocardiographic signs of coronary heart disease. Although peak systolic aortic valve gradient tended to decrease with increasing severity of coronary heart disease, the severity of aortic stenosis was not a reliable indicator of the presence of coronary disease. Patients with coronary heart disease in the absence of angina all had a combination of moderate aortic stenosis and single vessel disease. It is concluded that coronary heart disease cannot be predicted in patients with angina and, in the absence of angina occurs with an incidence sufficiently high to advocate the use of coronary angiography as part of the investigation of all patients with aortic stenosis being considered for valve replacement.

Severe aortic stenosis with impaired left ventricular function and clinical heart failure: results of valve replacement

Nineteen patients, aged 58-80 years, with severe isolated aortic valve stenosis, severely reduced ejection fraction and clinical heart failure underwent aortic valve replacement between January 1970 and April 1977. Ten had concomitant coronary artery disease (all underwent additional coronary bypass surgery), 17 had angina pectoris and four had syncope. Aortic valve area index was 0.32 +/- 0.03 cm2/m2 (mean +/- SEM); left ventricular (LV) end-diastolic volume index was 117 +/- 9 ml/m2 and LV ejection fraction was 0.37 +/- 0.02. There were four operative deaths and one late death. The follow-up time ranged from six to 74 months (38 +/- 6 months). Actuarially determined three-year survival is 74 +/- 10%; the expected five-year survival is the same. One patient had a serious cerebrovascular accident. Of the remaining survivors, seven were initially Functional Class IV and six Class III; currently, six are Class I and seven Class II (New York Heart Association classifications). The cardiothoracic ratio has decreased from 0.54 +/- 0.03 to 0.49 +/- 0.03. Repeat hemodynamic evaluation has been performed in 10 patients, 22 +/- 6 months after surgery. In these 10 patients, the aortic valve gradient decreased from 55 +/- 7 11 +/- 1.3 mm Hg; LV end-diastolic pressure from 22 +/- 2.4 to 9 +/- 1.9 mm Hg; LV end-diastolic volume index from 119 +/- 16 ml/m2 to 107 +/- 11 ml/m2. LV ejection fraction has increased dramatically from 0.34 +/- 0.03 to 0.63 +/- 0.05 and mean velocity of circumferential fiber shortening from 0.57 +/- 0.08 to 1.3 +/- 0.18 circ/sec. The encouraging long-term survival, improved functional class and the marked improvement in left ventricular function that occurred in our patients indicate that all patients with severe aortic stenosis in clinical heart failure should be offered aortic valve replacement.

Pre-infarction angina secondary to calcific aortic stenosis with Bernheim's effect

Pre-infarction angina, in the absence of coronary artery disease, was found in a 62 year-old man with severe calcific aortic stenosis. After application of intraaortic balloon pump counter-pulsation, the condition was stabilized, and coronary arteriograms were safely carried out. Interestingly, an elevated right atrial and right ventricular end-diastolic pressure with an associated Bernheim's effect was demonstrated by cardiac catheterization. The hemodynamics of the right heart returned to normal after surgical correction of the aortic stenosis. The clinical indications for intra-aortic balloon pump counterpulsation in this setting are discussed.

Technical considerations in patients undergoing combined aortic valve replacement and aortocoronary bypass surgery

Forty-nine patients have undergone combined aortic valve replacement and aortocoronary saphenous vein bypass graft surgery using a technique of distal coronary perfusion. Vein grafts are placed before replacement of the aortic valve, and continuously perfused by siting the proximal anastomoses high on the aortic root or individually perfusing the grafts before proximal anastomosis. Continuous coronary ostial perfusion is used as well during aortic valve replacement. There were 3 (6.1%) operative deaths and 1 (2%) perioperative myocardial infarction. A comparison of this technique with other reported results suggests that attention to myocardial perfusion distal to significant coronary artery stenosis may decrease the incidence of perioperative myocardial infarction in patients requiring both aortic valve replacement and coronary bypass graft operation.

Diagnosis and treatment of aortic valve stenosis

The present review has attempted to summarize the classic symptoms and signs of aortic valve stenosis, especially in an adult. It is emphasized that all the classic signs rarely are present and their absence may mislead an unwary clinician. The diagnostic help provided by noninvasive tests, including echocardiography and phonocardiography, has been emphasized. A need for cardiac catheterization and angiography in most patients prior to corrective surgery is stressed. The natural history of the disease without operative intervention is dim and a significant risk of sudden death exists. The current surgical approach with immediate and long-term results is summarized. Finally, attention has been drawn to the special clinical circumstances when the aortic valve stenosis provides a strinkingly different clinical picture. We cannot find a better way to end this review than by quoting a warning note given by Thomas Lewis in 1920: "It is the faint cry of an anguished and fast failing muscle, which, when it comes, all should strain to hear, for it is not long repeated. A few months, a few years at most, and the end comes."

Reversal of advanced left ventricular dysfunction following aortic valve replacement for aortic stenosis

A series of 12 consecutive patients who underwent aortic valve replacement (AVR) for aortic stenosis complicated by severe left ventricular dysfunction was reviewed. Ventricular dysfunction was reflected by pulmonary congestion, edema, renal and hepatic dysfunction, and by severely depressed ejection fractions (mean, 13%; range equal to 0-20%). Aortic valve replacement was accompanied by mitral commissurotomy in 1 patient and aortocoronary bypass in 5. Three of 5 patients with greater than 50% coronary obstruction died without reversal of heart failure, and 1 of the 5 died after a stroke. The 1 survivor of this group has done well. All 7 patients with minimal or no coronary disease survived operation and are now in New York Heart Association Class I or II. Postoperative catheterization (2 to 12 months) in 6 patients showed improved cardiac index and filling pressures. Left ventricular diastolic volume fell from 159 to 82 ml/m2, and ejection fraction rose from 13 to 45%. We conclude that left ventricular dysfunction owing to aortic stenosis alone is reversible and that AVR results in great clinical improvement. When coronary disease is present, survival may be accompanied by great improvement but the operative mortality is much higher.

Concomitant aortic valve replacement and myocardial revascularization

Twenty-six consecutive patients underwent combined aortic valve replacement and myocardial revascularization at the Emory University Affiliated Hospitals between May, 1973 and March, 1976. Acute myocardial infarction resulted in two operative deaths (8%). There have been four late deaths, all Class IV preoperative. The age range was 37 to 79 years with an average age of 60. Preoperatively all patients were Class IV or late Class III. Twenty-three patients had symptoms of angina pectoris; congestive heart failure was evident in 56%. Postoperatively, 70% are now Class 1 or II. Single coronary bypass was performed in 16 patients, double in 6, and triple in three. Double bypass plus mitral valve replacement was required in two with aneurysmectomy in one. The rate of intraoperative infarction was 27% for the series but only 7% in the last year. The methods of intraoperative myocardial preservation and the technical approach for the operative procedures were variable. Results with each method are correlated, and currently preferred techniques are presented and discussed. Best results were obtained in patients who presented early in their symptomatic course with isolated proximal coronary lesions and good renoff vessels. Excellent results could be achieved despite advanced age of patients, requirement for multiple bypass grafts, and correction of other associated cardiac lesions. Poorest results were obtained when long-standing ventricular failure was combined with poor vessels distal to coronary stenoses.

Frequency and significance of coronary arterial dominance in isolated aortic stenosis

Myocardial infarction during aortic valve replacement has previously been reported to result from obstruction of a branch of the left main coronary artery by the perfusion cannula. Patients with a dominant left coronary arterial system may be at greater risk. To assess the frequency and significance of a dominant left coronary arterial system the coronary angiograms of 75 consecutive patients more than 34 years of age with isolated aortic stenosis were studied and compared with those of a control group of 150 patients. Among the patients with aortic stenosis, 19 (25 percent) had left dominance, 9 (12 percent) a balanced circulation and 47 (63 percent) a dominant right coronary arterial system. Among control patients, 14 (9 percent) had left dominance 18 (12 percent) a balanced system and 118 (79 percent) right dominance. The increased prevalence of left dominance in patients with aortic stenosis was significant (P less than 0.005). Among patients with aortic stenosis, the left main coronary artery was shorter (P less than 0.01) in those with left dominance (6.2 +/- 1.3 mm [mean +/- standard error]) than in those with right dominance (9.9 +/- 0.7). Sixty-nine patients with aortic stenosis underwent aortic valve replacement. Perioperative myocardial infarction occurred in 4 of 15 (26.7 percent) of those with left dominance and in 4 of 54 (7.4 percent) of those with right dominance or a balanced circulation (P less than 0.05). Perioperative myocardial infarction occurred in all three patients with left dominance and obstructive coronary artery disease. The increased prevalence of a dominant left coronary arterial system in aortic stenosis suggests that this may be part of a developmental complex. Patients with left dominance have a shorter left main coronary artery than patients with right dominance. They also have an increased risk of perioperative myocardial infarction if there is associated obstructive coronary artery disease. Preoperative information about the coronary arterial anatomy and extent of coronary artery disease may be helpful in planning the use of coronary perfusion and other myocardial preservation techniques during surgery in order to reduce the incidence of myocardial infarction.

Aortic valve replacement combined with myocardial revascularization. Late clinical results and survival of surgically-treated aortic valve patients with and without coronary artery disease

From 1967 through 1973, 80 consecutive patients underwent simultaneous aortic valve replacement (AVR) and coronary bypass grafting. Fourteen (18%) experienced no angina pectoris and had no history or electrocardiographic evidence of coronary atherosclerosis. Seven of these 14 had severe multiple vessel disease. All operations were performed under normothermic conditions without coronary perfusion. Seven patients (9%) died during operation. Intra-operative myocardial infarction was documented in eight (10%). After a mean follow-up of 35 months, overall mortality was highest in aortic regurgitation patients [seven of 13 (54%)] compared to aortic stenosis [17 of 54 (31%)] (P less than 0.07), and mixed pathology [1 of 13 (8%)]. Thirty-one of 34 (91%) grafts in 25 patients were patent an average of 12 months postoperatively. After 42 months a 65% actuarial survival was found in the combined AVR and graft(s) series versus a 76% survival in 300 AVR patients proven by angiography not to have severe coronary atherosclerosis.

Combined procedure of coronary artery bypass grafting and valve repair

The safety of combined operative procedures for valvular and coronary artery disease was reviewed in 27 patients. Twelve patients had aortic valve disease and 15 had mitral valve disease. Forty-seven coronary artery reconstructions were performed, and average of 1.7 per patient. Twenty-two patients underwent valve replacement and 5 had valvuloplasty. Congestive heart failure was the major symptom in 20 patients, and angina was the major symptom in 7. Eight of the patients with congestive heart failure had no angina, but significant coronary stenoses were demonstrated at routine coronary angiography. Coronary reconstruction was performed before valve repair. Two patients died postoperatively (a hospital mortality of 7.4%), and there were 4 late deaths from 2 to 28 months postoperatively. There were no postoperative myocardial infarctions. Contrary to previous reports, coronary artery reconstruction and valve repair need not be associated with an increased risk. Protection of the myocardium by coronary perfusion through reconstructed coronary arteries enables valve repair to be done without greater risk than valve repair alone. All patients considered for valve repair should have coronary angiography.

Combined valvular and coronary artery surgery

Between July 1, 1971, and March 1, 1975, 45 patients underwent combined valvular and coronary artery operation. Aortic valve disease was present in 30 patients, mitral valve disease in 13, aortic and mitral valve disease in 1, and tricuspid valve disease in 1. The average age was 57 years. Seventeen patients were in New York Heart Association Functional Class IV. Seventeen patients had had a previous myocardial infarction. Significant coronary artery disease was an unexpected finding at the time of coronary angiography in 14 patients. The average number of grafts inserted was 2.5 per patient. The grafts were placed prior to valve replacement, and periods of myocardial ischemia were kept at a minimum by maintaining coronary perfusion throughout the operation. Operative mortality was 16%; late mortality was 8%. Perioperative myocardial infarction occurred in 2 patients.

Significance of angina pectoris in aortic valve stenosis

Of 60 patients aged 45 to 66 years with aortic valve stenosis, 28 (47 per cent) had angina pectoris. Significant coronary arterial obstruction was shown by selective coronary cineangiography in 14 of them. Systolic pressure gradients across the aortic valve were lower in patients with angina than in those without. In those with angina, systolic gradients were higher in those with normal coronary arteriograms than in those with demonstrable coronary arterial disease. Aortic valve replacement relieved the angina in all patients who had normal coronary arteriograms. When valve replacement was combined with coronary bypass grafting in those with coronary arterial disease, surgical mortality was higher and symptomatic relief less predictable. Incapacitating angina in patients with aortic stenosis was nearly always associated with significant coronary disease. In those with less severe angina it was impossible to predict the state of the coronary arteries. Two patients, who did not have angina and who did not undergo coronary arteriography, died after aortic valve replacement and were found at necropsy to have unsuspected severe coronary disease. We, therefore, suggest that coronary arteriography should be carried out in all patients over the age of 40 years in whom surgery is being considered for aortic stenosis.

Local deep hypothermia for combined valvular and coronary heart disease

Local deep hypothermia was utilized as the sole method of myocardial protection in 113 consecutive aortic valve replacements. Thirty-six patients had simultaneous revascularization, mitral valve replacement, tricuspid valve replacement, or a combination of these. In follow-up for as long as 36 months there have been 3 hospital deaths (2.6%), all occurring in the group having isolated aortic valve replacement. No hospital deaths occurred among patients undergoing a combined procedure.

Determinants of cardiac performance in severe aortic stenosis

Left ventricular (LV) myocardial function and the influence on LV pump performance of associated coronary arterial disease, of outflow obstruction and its consequences, and of altered ventricular pressure-volume characteristics were examined in a representative group of 28 adult patients with symptomatic severe aortic stenosis (valvular orifice area less than 0.50 sq cm/sq m). Eighteen patients (64%) exhibited depressed LV pump performance with levels of ejection fraction less than 0.50. In seven patients, coronary arterial disease documented by either arteriographic studies or postmortem analyses was associated with a segmental (i.e., nonhomogeneous) LV contractile disorder consistent with previous myocardial infarction. In the remaining 11 patients a homogeneous LV contractile disorder was the result of chronic outflow obstruction and its consequences. The possibility that reduced ventricular performance might be accounted for by increased afterload could not be supported by significant correlation between LV contractile characteristics (estimated from the ejection fraction and the mean circumferential fiber shortening rate) and indices of afterload (including LV systolic pressure, aortic valvular orifice area, and mean systolic wall tension). This observation suggested that myocardial hypertrophy and other consequences of longstanding obstruction to outflow played a primary role in depression of LV performance in these patients. Left ventricular end-diastolic volume was abnormal in all but three patients with depressed LV function; this increase was accompanied by a disproportionately greater increment in end-diastolic pressure, suggesting that reduced distensibility limited the ability of the ventricle to compensate for reduced contractile performance by means of the Starling mechanism.

Aortic stenosis, angina pectoris, coronary artery disease

The data from 88 patients (pts) with aortic stenosis (AS) were reviewed to determine relationships between angina pectoris (AP) and coronary artery disease (CAD). Results of surgery performed in 81 of these pts was analyzed. All pts had coronary arteriograms, and lesions greater than or equal to 50% were considered significant. Fifty-nine pts had an aortic valve gradient measured at catheterization greater than or equal to 40 mmHg, and in 29 pts, AS was confirmed at operation. Sixty-eight pts (77%) experienced AP, and 32 had coexisting CAD (47%); 9 of 20 pts without AP had CAD (45%). There were no significant differences in the incidence of AP in pts divided into subgroups by the aortic valve gradient (40-50, 51-100, 101-200 mmHg) or age (40-59, 60-81 years). Also, no significant differences were found in the incidence or extent of CAD between the two age groups; the extent of CAD was similar regardless of the presence or absence of AP. In pts with AP (1) CAD was more likely in pts greater than or equal to 60 years of age; (2) CAD was less likely when the aortic valve gradient was greater than 100 mmHg, suggesting that AP in these pts was due to hemodynamically severe AS. All pts with 3-vessel CAD experienced AP, and the aortic valve gradient was less in these pts than in those with no CAD or less extensive CAD. In 19 pts with combined AS and CAD who had both the aortic valve replaced and a revascularization operation only 1 of pts died in the hospital, while 3 of 19 pts with combined AS and CAD who had aortic valve replacement alone died. In this study a significant number of pts with AS experienced AP, and the presence or absence of AP did not predict coexisting CAD. Coronary arteriography is recommended in the evaluation of pts greater than or equal to 40 years of age with AS. The operative mortality appears to be decreased in pts with AS and CAD who have combined surgery.