Left ventricular pressure-volume relationships before and after cardiomyoplasty in patients with heart failure
Schreuder, J.J.; van der Veen, F.H.; van der Velde, E.T.; Delahaye, F.; Alfieri, O.; Jegaden, O.; Lorusso, R.; Jansen, J.R.; Hoeksel, S.A.; Finet, G.; Volterrani, M.; Kaulbach, H.G.; Baan, J.; Wellens, H.J.
Circulation 96(9): 2978-2986
1997
ISSN/ISBN: 0009-7322 PMID: 9386165 Document Number: 475861
Background. The aim of this study was to elucidate whether beneficial effects of cardiomyoplasty (CMP) in patients with dilated cardiomyopathy are the result of a decrease in existing ventricular dilatation or a prevention of further dilatation. Methods and Results. Combined micromanometer-conductance catheters were used to evaluate left ventricular pressure-volume relationships in six patients with dilated cardiomyopathy before and at 6 and 12 months after CMP. Acute changes in preload and afterload were induced by a standardized leg-tilting intervention and a bolus infusion of nitroglycerin. After CMP, end-diastolic volume (EDV) decreased from 138+-10 to 103+-18 mL/m2 (P<.01) at 6 months and to 83+-17 mL/m2 (P<.01) at 12 months. End-diastolic pressure (EDP) decreased from 20.2+-6.4 to 13.9+-7.7 mm Hg (P<.01) at 6 months after CMP. Peak ejection rate and ejection fraction increased at 6 months after CMP from 594+-214 to 799+-214 mL/s (P<.05) and from 26.6+-4.7% to 40.1+-8.3% (P<.05), respectively. Peak -dP/dt decreased at 12 months after CMP from -842+-142 to -712+-168 mm Hg/s (P<.05). Leg-tilting before CMP increased EDP from 20.2+-6.4 to 25.6+-5.2 mm Hg (P<.01), end-systolic pressure (ESP) from 118+-17 to 122+- 17 mm Hg (P<.05), and tau from 50.8+-2.8 to 53.8+-2.3 ms (P<.05). Six months after CMP, leg-tilting also increased EDV from 103+-18 to 110+-22 mL/m2 (P<.05) and ESV from 62+-14 to 66+-14 mL/m2 (P<.05). Before CMP, nitroglycerin decreased EDP from 20.2+-6.4 to 10.4+-3.8 mm Hg (P<.01), ESP from 118+-17 to 96+-11 mm Hg (P<.05), ESV from 100+-11 to 89+-7 mL/m2 (P<.05), and tau from 50.8+-2.8 to 44.5+-3.7 ms (P<.05). Six months after CMP, nitroglycerin decreased EDP, ESP, and tau to similar values. Conclusions. Our findings show that up to 1 year after CMP, marked decreases in left ventricular volume are present. Our measurements suggest that CMP actively reduced the dilated ventricle but did not prevent a higher EDV on an increased venous return. The latissimus dorsi muscle wrap contraction results in better synchronization of contraction and more rapid emptying of the left ventricle.