[Results of coronary surgery in mildly symptomatic patients with left ventricular dysfunction, multivessel disease and stenotic single residual patent vessel].
BACKGROUND
While efficacy of coronary artery bypass surgery in patients with depressed left ventricular function and myocardial ischemia is widely recognized, its results in patients in the absence of clinical evidence of myocardial ischemia remain uncertain. The purpose of this study was to evaluate the effects of coronary revascularization in comparison with conventional medical therapy in subjects with ischemic cardiomyopathy and myocardial ischemia presumed on the basis of angiographic anatomy but not demonstrated by functional testings.


METHODS
We selected retrospectively patients who underwent coronary angiography from 1986 trough 1993 and met the following criteria: presence of three-vessel coronary artery disease, occlusion of two and significant luminal narrowing (> or = 50%) of the third major epicardial artery, left ventricular dysfunction (ejection fraction < or = 40%), no angina or presence of mild angina, absence of inducible ischemia on exercise test and, when performed, of redistribution in the vascular territory of the patent vessel.


RESULTS
Thirty-one consecutive patients underwent isolated surgical revascularization treatment, while thirty medically treated patients with matched clinical characteristics were selected. Age (61 +/- 10 vs 62 +/- 9), gender (M/F 27/3 vs 24/7), NYHA class I-II (53 vs 62%) or NYHA III-IV (47 vs 38%), incidence of previous infarction (87 vs 94%), number of reversible defects in the vascular territory of the patient vessel on stress scintigraphy (0.6 vs 0.5), patent vessel (right coronary artery 7 vs 10; left circumflex 14 vs 12; left anterior descending 9 vs 9) and left ventricular ejection fraction (28 +/- 8 vs 31 +/- 7), were similar in the two groups (medical vs surgical). Surgically treated patients exhibited a lower proportion of overall cardiac deaths (7/31, 23% vs 19/30, 63%; p < 0.001), and more prolonged survival (67 +/- 9.3 vs 34 +/- 2.5 months; p = 0.04, Mantel and Cox test) than medically treated patients, respectively. The incidence of perioperative myocardial infarction was 10% (3/31). Causes of cardiac death were myocardial ischemia (9/19; 47%), sudden death (5/19; 26%) and heart failure (5/19; 26%) in medical patients, while were surgery (3 cases) and surgery related infection (1 case) (total 4/7; 57%), myocardial ischemia (1/7; 14%), sudden death (1/7; 14%) and heart failure (1/7; 14%) in surgical patients. Cox proportional hazard regression analysis with survival as the dependent variable, identified treatment, surgical or medical, as the best predictor of cardiac events (chi square improvement 9.36, p = 0.002). The next most powerful predictors were NYHA class and ACE-inhibitors treatment (chi square improvement 4.47 and 2.79, respectively).


CONCLUSIONS
In patients with left ventricular dysfunction, multivessel coronary artery disease and single patent but stenotic residual vessel, coronary artery bypass grafting appear to offer a better survival than medical therapy, even in the absence of clinically evident myocardial ischemia.
Dalle Mule
J
J
Divisione di Cardiologia, Ospedale Civile, Belluno.
Zingone
B
B
Bilardo
G
G
Sponga
B
B
Pellegrini
P
P
Branchini
B
B
Burelli
C
C
Zanuttini
D
D
Martinelli
F
F
Perelli
R
R
D000368:Aged; D016009:Chi-Square Distribution; D017023:Coronary Angiography; D001026:Coronary Artery Bypass; D003327:Coronary Disease / Q000188:drug therapy / Q000401:mortality / Q000601:surgery*; D004562:Electrocardiography; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D015996:Survival Rate; D013997:Time Factors; D018487:Ventricular Dysfunction, Left / Q000150:complications*
Risultati della chirurgia coronarica nei pazienti paucisintomatici con disfunzione ventricolare sinistra, malattia multivasale e unico vaso residuo pervio stenotico.