Effect of Left Ventricular Unloading by Pump Speed Adjustment on Myocardial Flow in Continuous-flow Left Ventricular Assist Device Patients.
Melana YuzefpolskayaAnnamaria LadanyiSabahat BokhariUlrich P JordePaolo C ColomboPublished in: ASAIO journal (American Society for Artificial Internal Organs : 1992) (2022)
Resting myocardial blood flow (MBF) and myocardial flow reserve (MFR) are reduced in heart failure (HF) patients supported by pulsatile left ventricular assist devices (LVADs). The effect of continuous-flow (CF) physiology on these parameters is underexplored in CF-LVAD patients. We investigated the impact of CF-LVADs on resting MBF and MFR under two left ventricular (LV) loading conditions. Nine HeartMate II patients (42 ± 12 years, 100% male) on support for 370 ± 281 days were enrolled. Results were compared with 9 HF patients (58 ± 13 years, 67% male, LV ejection fraction 27 ± 9%) and 10 healthy volunteers (56 ± 10 years, 20% male). CF-LVAD patients underwent transthoracic echocardiography with ramp study. MBF and MFR were measured utilizing positron emission/computed tomography imaging under two LV loading conditions: "high-speed" (HS), promoting aortic valve (AV) closure and LV unloading; "low-speed" (LS), promoting AV opening and LV loading. Global resting MBF was similar in HS, LS, HF, and healthy: 0.8 ± 0.3, 0.7 ± 0.3, 0.7 ± 0.1, 0.9 ± 0.2 ml/min/g, respectively; p = NS. HS global MFR was reduced compared with LS and HF: 1.6 ± 0.6 versus 1.9 ± 0.5, p = 0.004; 1.6 ± 0.6 versus 2.4 ± 0.5, p = 0.01, respectively. HS regional MFR was reduced compared with LS in the left anterior descending (1.7 ± 0.7 vs. 2.0 ± 0.6, p = 0.027) and left circumflex (1.8 ± 0.7 vs. 2.2 ± 0.9, p = 0.008), but not in right coronary artery (1.7 ± 0.7 vs. 1.7 ± 0.6, p = 0.76). Resting MBF is preserved among CF-LVAD patients and is similar to HF and healthy. Promoting LV ventricular unloading with higher speed was associated with lower global and regional left coronary MFR, while right coronary MFR did not change.
Keyphrases
- ejection fraction
- end stage renal disease
- left ventricular
- heart failure
- coronary artery
- computed tomography
- chronic kidney disease
- aortic stenosis
- newly diagnosed
- aortic valve
- peritoneal dialysis
- prognostic factors
- cystic fibrosis
- left ventricular assist device
- acute myocardial infarction
- blood flow
- magnetic resonance imaging
- patient reported outcomes
- positron emission tomography
- heart rate variability
- pulmonary arterial hypertension
- zika virus
- patient reported