Right ventricular volumes determined by computerized thermodilution in ischaemic heart disease: effect of exercise and nitroglycerin

• Published in: International journal of cardiology Vol. 33; no. 1; pp. 33 - 41
• Main Authors: Burger, Wolfram, Allroggen, Holger, Kober, Gisbert
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier Ireland Ltd 01.10.1991; Elsevier Science
• Subjects: Algorithms; Biological and medical sciences; Cardiac Catheterization; Cardiology. Vascular system; Coronary Disease - diagnosis; Coronary Disease - physiopathology; Coronary heart disease; Ejection fraction; Electrocardiography; Exercise; Exercise Test; Heart; Humans; Ischemic heart disease; Male; Medical sciences; Middle Aged; Nitroglycerin; Right ventricle; Thermodilution - methods; Thermodilution method; Ventricular Function, Right - drug effects; Ventricular Function, Right - physiology; Ischemic heart disease; Exercise; Thermodilution method; Right ventricle; Nitroglycerin; Ejection fraction; Physical exercise; Human; Cardiovascular disease; Exploration; Coronary heart disease; Thermodilution; Ischemia; Volume; Organic nitrate; Myocardium; Exercise tolerance test; Computer aid
• ISSN: 0167-5273; 1874-1754
• DOI: 10.1016/0167-5273(91)90149-J

In 29 patients with stable ischaemic heart disease, right heart catheterization was performed to assess the effect of exercise and nitroglycerin on right ventricular volumes, which were determined by a new computerized thermodilution system. The coefficient of variation for the determination of right ventricular ejection fraction averaged 11.0 ± 6.2% (mean ± standard deviation) at rest and 14.6 ± 8.1% during exercise. End-diastolic volume index increased from 90 (65–127) ml/m 2 [median (range)] at rest to 101 (81–130) ml/m 2 ( P ≤ 0.0001) during exercise. Nitroglycerin reduced this parameter at rest to 77 (44–121) ml/m 2 ( P ≤ 0.05), without affecting exercise values. Resting right ventricular ejection fraction (55 [44–64]%) was diminished by both exercise (to 52 [39–62]%, P ≤ 0.05) and nitroglycerin (to 53 [40–65]%, P ≤ 0.05). Additionally, nitroglycerin reduced the exercise induced decrease of right ventricular ejection fraction from −3 (-20-10)% to −1 (-15-14)% ( P ≤ 0.01). Nitroglycerin diminished the left-to-right interventricular end-diastolic pressure gradient, which was estimated from the difference between pulmonary capillary wedge pressure and right atrial pressure, at rest from 6 (1–17) mmHg to 5 (2–14) mmHg ( P ≤ 0.05) and during exercise from 17 (6–31) mmHg to 14 (1–33) mmHg ( P ≤ 0.001). It is concluded, that both exercise and nitroglycerin cause significant changes in right ventricular volumes. During exercise-induced myocardial ischemia, however, the expected decrease of right ventricular end-diastolic volume after nitroglycerin may be counterbalanced by a leftward displacement of the septum, which occurs due to a comparatively higher reduction in left than in right ventricular end-diastolic pressure. Furthermore, the computer assisted thermodilution method is a suitable method for determinations of right ventricular volume in ischaemic heart disease, both at rest and during exercise.