Dynamic ventricular dyssynchrony: an exercise-echocardiography study.
OBJECTIVE
We sought to assess the effects of exercise on ventricular dyssynchrony in patients with normal and depressed left ventricular (LV) function.


BACKGROUND
Asynchronous myocardial contraction adversely influences ventricular function and is associated with a poor prognosis in heart failure. Exercise-induced changes in ventricular dyssynchrony may be an important determinant of dynamic changes in cardiac output and mitral regurgitation.


METHODS
A total of 65 consecutive heart failure patients and 50 matched healthy control patients underwent exercise echocardiography. Conventional and tissue Doppler parameters were measured before and during symptom-limited exercise. Left ventricular dyssynchrony was defined as the standard deviation of 12 LV segmental electromechanical delays. Analysis of the control group allowed delimitation of normal cutoff values.


RESULTS
In patients with normal left ventricular function, exercise did not modify the extent of LV asynchrony. In contrast, in heart failure patients, LV dyssynchrony increased by at least 20% in 34%, remained stable in 37%, and decreased by at least 20% in 29%. Moreover, 26% of heart failure patients had either exercise induction or normalization of ventricular dyssynchrony. A significant association was found between exercise-induced changes in dyssynchrony and the presence of ischemic cardiomyopathy (p < 0.05). Rest-exercise differences in ventricular dyssynchrony were correlated with changes in cardiac output and mitral regurgitation (r = -0.63 and 0.56, respectively).


CONCLUSIONS
In heart failure patients, exercise can alter the magnitude of ventricular dyssynchrony. Some patients have a response to exertion with induction of ventricular dyssynchrony, whereas others show normalization. Changes in ventricular dyssynchrony during exercise correlate with alterations in cardiac output and mitral regurgitation.
Lafitte
Stephane
S
Cardiologic Hospital, Pessac and Bordeaux 2 University, Bordeaux, France.
Bordachar
Pierre
P
Lafitte
Marianne
M
Garrigue
Stephane
S
Reuter
Sylvain
S
Reant
Patricia
P
Serri
Karim
K
Lebouffos
Valerie
V
Berrhouet
Marianne
M
Jais
Pierre
P
Haissaguerre
Michel
M
Clementy
Jacques
J
Roudaut
Raymond
R
DeMaria
Anthony N
AN
D000368:Aged; D002303:Cardiac Output, Low / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology; D016022:Case-Control Studies; D004452:Echocardiography; D015444:Exercise; D005080:Exercise Test; D006801:Humans; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology; D011446:Prospective Studies; D015203:Reproducibility of Results; D012146:Rest; D018487:Ventricular Dysfunction, Left / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology*