Exercise training after anterior Q wave myocardial infarction: Importance of regional left ventricular function and topography

Abstract

To determine whether the extent of left ventricular dysfunction and the degree of shape distortion can predict outcome in survivors of moderate-sized anterior Q wave myocardial infarction who are undergoing exercise training, these variables were measured by two-dimensional echocardiography before and after 12 weeks of a low level exercise training program starting 15 weeks after infarction in 13 patients (7 in group 1 and 6 in group 2) and 12 weeks apart in 24 matched control patients without training. By the end of training, the functional class score had increased in group 2 (from 2.25 to 2.67, p less than 0.005) but had not changed in group 1. Further discrimination of groups 1 and 2 was provided by an initial asynergy (akinesia or dyskinesia, or both) less than 18% or greater than or equal to 18%. Compared with group 1, group 2 had greater initial asynergy (32 versus 6%, p less than 0.001), expansion index (asynergic/normal endocardial segment length: 1.8 versus 1.6, p less than 0.025) and peak shape distortion index (12.2 versus 1.0 mm, p less than 0.005) but lower ejection fraction (43 versus 59%, p less than 0.05) and thinning ratio (asynergic/normal wall thickness: 0.61 versus 0.74, p less than 0.05). These variables did not change with training in group 1. However, in group 2, training caused significant increase in asynergy (from 32 to 40%, p less than 0.05), expansion index (from 1.8 to 2.0, p less than 0.01) and peak shape distortion (from 12.2 to 20.9 mm, p less than 0.05) associated with a decrease in thinning ratio (from 0.61 to 0.51, p less than 0.001) and ejection fraction (from 43 to 30%, p less than 0.005). Initial values for these variables were similar for corresponding control groups but did not change over the 12 weeks. Thus, patients with greater than or equal to 18% left ventricular asynergy on the initial echocardiogram showed more shape distortion, expansion and thinning before exercise training and developed further functional and topographic deterioration with training.

Effect of endurance exercise training on morphological changes in rat heart tissue following experimental myocardial infarction

“…In other words, endurance training following infarction, resulted in enhancement of cardiac hypertrophy. Previous studies have shown that endurance training after MI can have a beneficial effect (9,13,14), without affecting (6, 7, 10, 12) or adverse effects (11,15) on cardiac function and remodeling. The results of this study showed that endurance training running on a treadmill after MI increased the rate of necrosis damage and infarct size compared with the control group (no training).…”

“…Serra et al (2010) suggested that 13-weeks of endurance training in rats, prevents adverse remodeling of LV that was caused by the injection of isoprenaline (14). Jugdutt et al (1988) claimed that 12-week low-intensity exercise after MI may trigger remodeling of LV, expansion of MI, further scar thinning and reduction of ejection fraction (15). In summary, many studies have been done with respect to the effects of endurance exercise training on cardiac remodeling after MI in animal and human subjects.…”

Influence of aerobic exercise training on left ventricular remodeling and neurohumoral response in patients with myocardial infarction

“…Over the last decades several scientific works were published, which sought to assess the effects of the aerobic physical exercise on VR and the cardiac function of patients suffering from MI, who evolved with LV systolic dysfunction [7][8][9][10][13][14][15][16]. Many of these studies, considered classics and pioneers, continue to be cited in various scientific articles and are selected for composing meta-analyses, despite having been conducted at a time when blocking of neurohumoral activation after MI was not understood as the cornerstone of the treatment of ventricular dysfunction.…”

Effects of Exercise Training on Left Ventricular Function Evaluated by the Tei Index in Patients With Myocardial Infarction

“…Ornish et al found that patients in the exercise group demonstrated improved LVEF during peak exercise, 7 but Jugdutt et al reported that patients with lower LVEF developed further functional and topographic deterioration with exercise training. 6 Giannuzzi et al 5 reported that in the in EAMI trial post infarction patients without clinical complications, even those with a large infarction, had a possible benefit from long-term physical training without any additional negative effect on ventricular size or topography. Recently, Otsuka et al reported that patients with moderate to severe LV dysfunction benefited from exercise training started early after AMI without any deterioration in LV remodeling, with a similar magnitude of improvement in exercise capacity to that in patients with mild LV dysfunction.…”

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everal studies have reported the influence of exercise training on left ventricular (LV) contractility in patients with myocardial infarction (MI), although consensus has not been obtained; no changes in resting contractility were observed, 1-4 improvement was achieved only in patients with cardiac dysfunction, 5 deterioration was observed only in patients with cardiac dysfunction, 6 LV ejection fraction (LVEF) during exercise improved. 7,8 The present study was conducted to investigate the influence of exercise training on LV function and exercise tolerance in patients with acute MI (AMI) using a new index of cardiac function, the Tei index.

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