Coronary Flow Velocity and Coronary Flow Velocity Reserve in Children with Ventricular Septal Defect

Abstract

HARADA, K., AOKI, M., TOYONO, M. and TAMURA, M. Coronary Flow Velocity and Coronary Flow Velocity Reserve in Children with Ventricular Septal Defect. Tohoku J. Exp. Med., 2004, 202 (2), 77-85 To assess coronary flow characteristics in congenital heart defect with left ventricular (LV) volume overload, we examined 24 children (mean 12.1±7.1 months) with ventricular septal defect. The pulmonary to systemic flow ratio ranged from 1.1 to 3.0. Control group consisted of 10 age-matched children who had a history of Kawasaki disease with angiographically normal coronary artery in the acute phase. LV end-diastolic volume and LV mass were measured by left ventriculogram. With Doppler flow guide wire (0.014-inch), average peak flow velocity (APV) in left anterior descending coronary artery was recorded at rest and during hyperemia (0.16 mg/kg/min adenosine infusion intravenously). Coronary flow velocity reserve (CFVR) was calculated as the ratio of hyperemic/baseline APV. Seven patients were also studied 5-7 months after surgery. Compared with control subjects, CFVR was significantly reduced in patients with LVvolume overload (1.78±0.24 vs. 2.66±0.42, p<0.0001) because baseline APV was significantly greater (30±8 vs. 23±5 cm/sec, p=0.0027). Significant correlations were observed between CFVR and Qp/Qs, baseline APV, LV end-diastolic volume, or LVmass. Stepwise regression analysis showed that baseline APV and Qp/Qs were important determinants of CFVR (CFVR=2.64−0.202 [Qp/Qs]−0.015 [APV] r=0.83, p<0.0001). In 7 patients with LVvolume overload, CFVR improved significantly after surgery because of reduction of baseline APV. CFVR is limited in patients with LV volume overload because of the elevation of baseline resting APV. LAD flow pattern is dependent on LV volume overload level and its changes after surgery. ventricular septal defect; coronary flow velocity reserve

Effects of cardiopulmonary bypass surgery on coronary flow in children assessed with transthoracic Doppler echocardiography

“…Because there is a certain maximal dilatory state that can be reached, it is conceivable to assume that an increase in CF may lead to impaired CFR (38). Therefore, our findings support earlier studies by positron emission tomography (PET) and intracoronary Doppler guide wire (IDGW) showing a drop in CFR after CBP surgery (7,13). In contrast, surgical off-pump correction of aortic coarctation resulted in decrease of both myocardial oxygen consumption and coronary flow, which implies either that off-pump surgery has little or no effect on the coronary flow or that the removal of pressure overload after coarctectomy counteracts possible detrimental effects of off-pump surgery on coronary flow.…”

Prospective Assessment of Coronary Artery Flows Before and After Cardiopulmonary Bypass in Children With a Spectrum of Congenital Heart Disease

“…15,23,24 Coronary flow reserve in a variety of congenital cardiac lesions (VSD, TGA, tetralogy of Fallot, hypoplastic left heart syndrome) is lower than in adults. [25][26][27][28][29] These findings are similar to ours, where the CFR in all groups was <2.2. The lower CFR may be due to the observed higher basal coronary flow with a more blunted hyperaemic response.…”

Coronary flow before and after surgical versus device closure of atrial septal defect

“…Positron emission tomography technique has shown it to be decreased 1-3 weeks after surgery on CPB [2]. Intracoronary Doppler flow guide wire (IDGW) studies done 5-7 months after surgery showed improved but still low CFR as compared to presurgical values [7].…”