Does the Completeness of Revascularization Contribute to an Improved Early Survival in Patients up to 70 Years of Age?[∗]

Objective: In the era of a renewal of incomplete revascularization approaches, the controversy reappears as to whether the approach for complete revascularization is of prognostic value. The clear advantage of complete revascularization in elderly patients has recently been published. However, for the younger patient group, there is no conclusive information available so far. The aim of our study was to investigate the effect of complete vs. incomplete revascularization in patients up to 70 years of age. Patients and Methods: 6531 patients underwent isolated CABG. 5003 of these patients were aged up to 70 years at the time of operation. Results: Incomplete revascularization was performed in 534 (10.7 %) patients. The most common reasons for incomplete revascularization were small vessels and massive calcification. The differences in mortality up to the 180^th day after CABG are statistically significant. By Kaplan-Meier analysis, the time relationship between incomplete revascularization and death affects predominantly the very early period after CABG. By logistical regression, incomplete revascularization was found to be an independent risk factor for death after CABG. Conclusion: Incomplete revascularization affects the early outcome after CABG in patients up to 70 years of age as an independent risk factor for death. In view of recent approaches for primarily incomplete CABG, our results indicate the necessity to reconsider the advantages of complete revascularization.

Coronary artery bypass grafting - Incomplete revascularization - Younger patients

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1 Presented at the 30^th Annual Meeting of the German Society for Cardiac, Thoracic and Vascular Surgery, Leipzig, Germany, Feb 18-21, 2001

Appendix A

Variables included in the logistic regression model:

Demographic

Gender, Age (years) at operation, weight, height, body mass index, obesity (men: height in cm - 90, women: height in cm - 100)

Cardiac comorbidity

NYHA (l = mild, 2 = mild symptoms, 3 = symptoms with normal activities, 4a = severe with symptoms at rest, 4b = unstable angina), Holper (l = mild, 2 = mild symptoms at higher degree of physical stress, 3 = symptoms at mid degree of physical stress, 4 = symptoms at low degree of physical stress, 5 = stable out of unstable angina, 6 = beginning unstable angina, 7 = unstable angina, 8 = cardiogenic shock), severe heart failure in history, subjective impression of heart failure, clinical sign of heart failure, dyspnea at exercise, dyspnea at rest, exercise-related angina, angina at rest, treatment for unstable angina (0 = neither oral, nor i. v.-medication. l = oral medication, 2 = intravenous medication), pathologic valvular findings without necessity for surgical treatment, urgency of operation (elective, urgent, emergent, emergent + CPR)

Left ventricular function

Normal left ventricular size, left ventricular hypertrophy, left ventricular dilatation, left ventricular hypokinesia, left ventricular akinesia, left ventricular aneurysm, systolic aortic pressure, diastolic aortic pressure, mean aortic pressure, left ventricular systolic pressure, left ventricular end diastolic pressure, left ventricular function qualifier (0 = good, l = fair, 2 = bad). Ejection fraction was available for only 63 % of all patients, acute myocardial infarction, chronic pulmonary edema, acute pulmonary edema, cardiogenic shock

Preoperative drugs

Diuretics, ACE inhibitors, antibiotics, aspirin, digitalis, β-blocker, calcium antagonists, anticoagulation, antiarrhythmic agents, any preoperative drug

Non-cardiac comorbidity

Smoking, diabetes, hyperlipoproteinemia, hypertension, hyperuricemia, positive family history, any of the known “risk” factors, syncope, embolism, gastrointestinal disease, extracardiac vascular disease, calcified aortic wall, pulmonary obstructive disease, pulmonary restrictive disease, any pulmonary disease, renal disease, dialysis dependency, neurological disease

Coronary status

Number of affected vessels, diffuse arteriosclerotic affection of coronary arteries, left main disease, dominant vessel, number of coronary vessels disease > 50 %, > 70 %, > 90 %, 100 % stenosis, number of coronary systems disease > 50 %, > 70 %, > 90 %, 100 % stenosis, stenosis of LAD > 50 %, > 70 %, > 90 %, 100 %, stenosis of RCA > 50 %, > 70 %, > 90 %, 100 %, stenosis of Circumflex artery > 50 %, > 70 %, > 90 %, 100 %, diagonals

Preoperative rhythm

Sinus rhythm, atrial fibrillation, ventricular tachycardia, pacemaker, ventricular ectopic beats

Previous procedures

PTCA, coronary stent implantation, laser ablation, complication of PTCA, unsuccessful PTCA, bypass occlusion, bypass stent implantation, thrombolytic therapy (within the last 14 days), reoperation for CABG, number of previously performed CABG procedures.

Surgical strategy

Use of IMA, incomplete revascularization, surgeon