Recently, a considerable percentage of patients with valvular heart disease also have coronary artery disease requiring coronary revascularization during valvular operation, due to the increasing number of elderly patients in the general population, the improving safety of coronary artery bypass grafting (CABG), the increasing incidence of coronary artery disease, and the higher mortality rate after acute myocardial infarction, an incidence of which may be reduced by CABG.1 Combined valvular heart surgery and CABG had a substantially higher hospital mortality than those having either procedure alone, which ranged from 7% to 18%.2-9 Since there have not been many reports about this issue, we reviewed the clinical results of our 15-year experience of combined valvular heart operations and coronary revascularization to evaluate the clinical results, and to determine if co-existing coronary artery disease affected long-term survival.

Among 125 patients, 6 patients had previous open-heart operations (2 had previous CABG, 1 had MVR, 1 had mitral valvuloplasty, and 2 had ASD patch repair). Among the patients who had mitral valve surgery, 19 received a mechanical prosthesis, 7 received a biological prosthesis, and 28 had a mitral valve repair. Among the patients who had aortic valve surgery, 29 received a mechanical prosthesis, 26 received a biological prosthesis, 4 had an aortic valve repair, and 2 had a Bentall procedure. Valvular operations performed are described in Table 1. Preoperative mean left ventricular ejection fraction was 56.9% and 74% of patients were NYHA functional class III or IV. The distributions of coronary artery disease according to the age and sex are shown in Figs. 1 and 2.

Preoperative risk factors for coronary artery disease included diabetes mellitus in 32 patients, hypertension in 60 patients, smoking in 63 patients, obesity in 5 patients, family history of coronary artery disease in 2 patients, and hypercholesterolemia in 33 patients (Table 2). Seventy-five percent of patients had a Canadian Class III or IV chest pain. Coronary revascularization was performed in all patients with a mean of 2.0 distal grafts/patient. Left internal mammary artery (IMA) was used in 84 patients (67%), right IMA in 2 patients, and bilateral IMA in 1 patient. Intraoperative data are described in Table 3.

The overall hospital mortality was 4.8% (6/125 patients). The causes of early death were low cardiac output due to left ventricular failure in 4 patients and septic multi-organ failure in 2 patients. Postoperative complications included CVA in 2 patients, ARF requiring dialysis in 5 patients, reexploration for bleeding in 3 patients, IABP insertion due to low cardiac output in 2 patients, wound infection in 3 patients, pneumonia in 2 patients, and perioperative MI in 1 patient. Postoperative LV EF increased from 56.9 ± 14.2 to 58.6 ± 11.07% without statistical significance (p = 0.09). Postoperative Canadian (2.33 ± 0.85 to 1.13 ± 0.45, p < 0.05) and NYHA functional class (2.84 ± 0.60 to 1.29 ± 0.57, p < 0.001) improved significantly. The mean follow-up duration was 91.4 ± 40.9 months (range: 47-245 months), and late mortality occurred in 4 patients during the follow-up period. The causes of late deaths were cardiac related in one patient (sudden death) and non-cardiac related in 3 patients (CVA, malignancy, and sepsis). Two patients required a reoperation during the follow-up period, and the causes of reoperations were residual severe aortic regurgitation 19 months after aortic valvuloplasty in one patient and paravalvular leakage of the previous mechanical prosthesis after 86 months of mechanical prosthetic valve implantation in mitral position in the other patient. Three patients developed CVA and 3 patients developed lung cancer. Among the three patients who developed lung cancer, 1 patient died and 2 patients are currently undergoing chemotherapy. Six patients were readmitted for cardiac related problems (recurred angina in 3 patients, congestive heart failure in 1 patient, and arrhythmia in 2 patients). In all three patients with recurred angina, a follow-up coronary angiogram showed patent grafts with progression of native coronary artery disease that was successfully treated with medication. Independent predictors of in-hospital death were age, presence of diabetes, preoperative renal insufficiency, and prolonged ICU stay (Table 4). Kaplan-Meier estimated survival rates at 1, 5, and 10 years were 94.4%, 92.3%, and 89.9%, respectively, and freedom from MACE (major cardiovascular event) rates at 1, 5, and 10 years were 93.6%, 89.7%, and 76.4%, respectively.

The combined valvular and coronary artery disease is increasing, and the increasing numbers of patients suffering from such coexisting diseases have been offered cardiac surgery. The most important reason for this is the aging of the population of patients being candidates for CABG.4,10 In addition, the operative therapy of patients with combined valvular and coronary artery disease has evolved significantly since the early 1970s when the first cases were performed and routine coronary angiography was advocated for all patients with valve disease.

Approximately 8 percent of patients undergoing cardiac surgery have combined valvular and coronary artery disease worldwide.11,12 Even though ischemic symptoms such as angina are important indicators of coronary artery disease, angina is a less specific indicator of coronary artery disease in patients with valvular heart disease than in the general population. Because ischemic symptoms in patients with valvular heart disease may have other causes such as left ventricular chamber enlargement, increased wall stress, or wall thickening with subendocardial ischemia and right ventricular hypertrophy.

Currently, ACC/AHA practice guidelines recommend coronary angiography for preoperative evaluation in patients with anginal symptoms, other objective evidence of ischemia, decreased LV systolic function, history of coronary artery disease, or coronary risk factors. In asymptomatic patients, coronary angiography is recommended in men older than 45 years and women older than 55 years.13 Since 1980, our institute adopted a policy of obtaining coronary arteriography before valvular operations in patients over the age of 40 in men and 45 in women, and of performing CABG and valvular repair or replacement at the same time. In this study, no patient less than 50 years old had combined coronary artery disease in women; however, in male patients, 12% (10/86) of patients were less than 50 years old, and 4 patients were in their 30s. The prevalence of premature coronary disease was reported to be 2-11% of all hospitalized myocardial infarcts described in the literature.14-18 And in the most recent series, an increase of incidence, probably due to earlier exposure to some risk factors, such as smoking habit, hyperlipidemia, and stress as a result of rapid changing of diet habits, and life-styles which facilitate development of coronary artery disease in young patients, have been reported.16-18 Therefore, a coronary angiography should be considered even in younger patients with risk factors, especially for men and postmenopausal women. In addition, less expensive and noninvasive diagnostic tools such as multi-detector-row helical computed tomography (MDCT), a simple, useful, and accurate method to evaluate concomitant coronary artery disease, might be a good alternative in these patients, if appropriately selected.19,20

In this study, we excluded the patients with ischemic MR since that is thought to be a different disease entity, which results in higher mortality. In patients with ischemic MR, the diseases of the coronary artery and valve are not combined; rather the valvular heart disease is the result from the coronary artery disease. Therefore, the result of valvular heart surgery regardless of the type of surgery is often affected by the extent or the surgical results of the coronary artery disease.

During the study period of fifteen years, 4,276 valvular and 4,457 coronary operations were performed in our institute, and only 1.4% of the patients underwent combined coronary and valvular operations, which is less than other reported series.11,12 The exact reason was not known; however, we speculated that it may be because the percutaneous coronary intervention (PCI) ratio to coronary artery surgery is higher in our institute, almost 10 to 1, and primary or secondary PCI might have been tried before or after the valve operations in some patients with high risks. Also the cardiologists might have been reluctant to recommend surgery in these patients because of the high expected mortality and morbidity especially during 1980s and early 1990s. For example, about 40% of patients with symptomatic severe aortic stenosis older than 65 years were never referred to surgery during the same period. However, the referring rates in these patients are increasing, and even though the mortality rate was still higher than the isolated procedures, this study showed that the clinical results in these patients were promising with satisfactory long-term survival.

In this study, the early mortality of the patient was higher than the patients with isolated valvular or coronary artery disease, respectively. However, the early surgical results have been improving since 2000 as a result of improvement of surgical technique, better understanding of myocardial protection, and postoperative management. Among 125 patients, 56 patients (45%) were operated on after the year 2000, and only 1 of these patients died in the immediate postoperative period (1.8%), which was reduced from 7.2% (5/69) of mortality rate before 2000. In addition, the long-term mortality for isolated valvular heart and coronary artery disease were reported to be 78-92%21-23 and 48-95%24-26 at 10 years, which meant that the long term survival for concomitant coronary and valve operation is comparable to those of isolated coronary or valvular operations. Therefore, surgical management should be considered for the primary treatment in patients with a coexisting coronary artery and valvular heart disease.