Open AccessHemodynamics and myocardial oxygen metabolism of pulsus alternans in patients with dilative cardiomyopathy
Author(s) -
Hasenfuss G.,
Holubarsch C.,
Heiss H. W.,
Bonzel T.,
Funfack M.,
Revenaugh M.,
Meinertz T.,
Just H.
Publication year - 1987
Publication title -
clinical cardiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.263
H-Index - 72
eISSN - 1932-8737
pISSN - 0160-9289
DOI - 10.1002/clc.4960100506
Subject(s) - medicine , cardiology , enoximone , preload , beat (acoustics) , cardiomyopathy , heart rate , blood pressure , hemodynamics , anesthesia , heart failure , physics , acoustics
The hemodynamic and myocardial energetic changes due to pulsus alternans were investigated by left and right heart catheterization and by oxygen consumption measurements in three patients with dilative cardiomyopathy. In all three patients, pulsus alternans developed after intravenous administration of the phosphodiesterase inhibitor enoximone. Following enoximone (Patients 1/2/3), left ventricular peak systolic pressure was reduced, in the respective patients, from 100/103/115 mmHg (normal beat) to 91/96/94 mmHg (strong beat) and further to 59/80/85 mmHg (weak beat); left ventricular end‐diastolic pressure was reduced from 24/23/22 mmHg (normal beat) to 5/10/6 mmHg (strong beat) and further to 3/7/4 mmHg (weak beat). Cardiac output increased by an average of 16%. Heart rate increased by an average of 12%. Stroke work (during pulsus alternans mean between strong and weak beats) did not change (<5%) in any of the three patients. Arterial‐coronary‐sinus oxygen content difference decreased by 5%/13%/22%, respectively. Myocardial oxygen consumption per beat decreased in Patient 1 by 18%, in Patient 2 by 8% and remained unchanged in Patient 3. It is concluded that pulsus alternans occurred in consequence of alternating systolic performance. The alternation in systolic performance most probably resulted from a disturbance in excitation‐contraction coupling induced by enoximone. The pronounced reduction of left ventricular preload following administration of enoximone may have augmented further the differences between the strong and the weak beat. A disturbance in myocardial oxygen metabolism was ruled out as the cause of pulsus alternans in these patients.