Coronary collateral flow in response to endurance exercise training

Abstract

Background In humans, it is not known whether physical endurance exercise training promotes coronary collateral growth. The following hypotheses were tested: the expected collateral flow reduction after percutaneous coronary intervention of a stenotic lesion is prevented by endurance exercise training; collateral flow supplied to an angiographically normal coronary artery improves in response to exercise training; there is a direct relationship between the change of fitness after training and the coronary collateral flow change. Methods and results Forty patients (age 61 ± 8 years) underwent a 3-month endurance exercise training program with baseline and follow-up assessments of coronary collateral flow. Patients were divided into an exercise training group (n = 24) and a sedentary group (n = 16) according to the fact whether they adhered or not to the prescribed exercise program, and whether or not they showed increased endurance (V o 2max in ml/min per kg) and performance (W/kg) during follow-up versus baseline bicycle spiroergometry. Collateral flow index (no unit) was obtained using pressure sensor guidewires positioned in the coronary artery undergoing percutaneous coronary intervention and in a normal vessel. In the vessel initially undergoing percutaneous coronary intervention, there was an increase in collateral flow index among exercising but not sedentary patients from 0.155 ± 0.081 to 0.204 ± 0.056 (P=0.03) and from 0.189 ± 0.084 to 0.212 ± 0.077 (NS), respectively. In the normal vessel, collateral flow index changes were from 0.176 ± 0.075 to 0.227 ± 0.070 in the exercise group (P=0.0002), and from 0.219 ± 0.103 to 0.238 ± 0.086 in the sedentary group (NS). A direct correlation existed between the change in collateral flow index from baseline to follow-up and the respective alteration of V o 2max (P=0.007) and Watt (P=0.03). Conclusion A 3-month endurance exercise training program augments coronary collateral supply to normal vessels, and even to previously stenotic arteries having undergone percutaneous coronary intervention before initiating the program. There appears to be a dose–response relation between coronary collateral flow augmentation and exercise capacity gained.

Coronary Collateral Growth Induced by Physical Exercise

“…Buschmann and colleagues 16 were able to show a significant increase in collateral formation after 7 weeks of intermittent external counterpulsation in 23 patients with stable CAD in comparison with an inactive control group. An increase of collateral blood flow was detected by Zbinden in a nonrandomized clinical trial in 40 patients 10 following regular physical exercise, performed 3 times a week over 3 months. However, PCI of the diseased vessel was performed before exercise training was initiated, which eliminated any possible ischemic trigger of collateral formation.…”

“…On the other hand, hemodynamic improvement of collateral blood was detected in a small nonrandomized study after 3 months of exercise training. 10 The Impact of Intensive Exercise Training on Coronary Collateral Circulation in Patients With Stable CAD (EXCITE) trial was designed as a proof-of-concept study to test the hypothesis that 4 weeks of intensive exercise training in comparison with usual care alone leads to an increase in collateral blood flow and thus improves the clinical status in patients with stable CAD. We further used 2 different exercise training intensities (highintensity training versus moderate-intensity training) to assess the impact of exercise intensity on the collateral blood flow.…”

Exercise Promotes Collateral Artery Growth Mediated by Monocytic Nitric Oxide

“…Other groups have alluded to a beneficial effect of exercise on coronary 33 or cerebrovascular 34 vascular growth. In these vascular territories, exact mechanisms of exercise-induced vascular growth are yet to be elucidated and may be comparable with those identified here.…”

Assessment of the Human Coronary Collateral Circulation

“…63 Matrix dissolution occurs, and the vessels undergo a growth process with active proliferation of their endothelial and smooth muscle cells. In this context, several candidates for effective coronary collateral arteriogenesis have been found recently in small but controlled clinical trials: granulocyte-monocyte colony-stimulating factor (which may not be safe enough, however), 64,65 granulocyte colony-stimulating factor, 12 physical endurance exercise training, 66 and external counterpulsation triggered by the ECG to occur during diastole. 13,67 …”