Early patency of the infarct-related artery after myocardial infarction preserves diastolic filling

The Impact of Sonothrombolysis on Left Ventricular Diastolic Function and Left Atrial Mechanics Preventing Left Atrial Remodeling in Patients With ST Elevation Acute Myocardial Infarction

BACKGROUND

The diagnostic ultrasound-guided high mechanical index impulses during an intravenous microbubble infusion (sonothrombolysis) improve myocardial perfusion in acute ST segment elevation myocardial infarction, but its effect on left ventricular diastolic dysfunction (DD), left atrial (LA) mechanics and remodeling is unknown. We assessed the effect of sonothrombolysis on DD grade and LA mechanics.

METHODS

One hundred patients (59 ± 10 years; 34% women) were randomized to receive either high mechanical index impulses plus percutaneous coronary intervention (PCI) (therapy group) or PCI only (control group) (n = 50 in each group). Diastolic dysfunction grade and LA mechanics were assessed immediately before and after PCI and at 48 to 72 hours, 1 month, and 6 months of follow-up. Diastolic dysfunction grades were classified as grades I, II, and III. The LA mechanics was obtained by two-dimensional speckle-tracking echocardiography-derived global longitudinal strain (GLS).

RESULTS

As follow-up time progressed, increased DD grade was observed more frequently in the control group than in the therapy group at 1 month and 6 months of follow-up (all P < .05). The LA-GLS values were incrementally higher in the therapy group when compared with the control group at 48 to 72 hours, 24.0% ± 7.3% in the therapy group versus 19.6% ± 7.2% in the control group, P = .005; at 1 month, 25.3% ± 6.3% in the therapy group versus 21.5% ± 8.3% in the control group, P = .020; and at 6 months, 26.2% ± 8.7% in the therapy group versus 21.6% ± 8.5% in the control group, P = .015. The therapy group was less likely to experience LA remodeling (odds ratio, 2.91 [1.10-7.73]; P = .03). LA-GLS was the sole predictor of LA remodeling (odds ratio, 0.79 [0.67-0.94]; P = .006).

CONCLUSION

Sonothrombolysis is associated with better DD grade and LA mechanics, reducing LA remodeling.

Combined systolic and diastolic dysfunction in the presence of preserved left ventricular ejection fraction

BACKGROUND

Heart failure with preserved left ventricular ejection fraction (LVEF) suggests isolated diastolic dysfunction.

AIM

The purpose of this study was to determine if systolic and diastolic dysfunction occurred with preserved LVEF.

METHODS

Equilibrium resting radionuclide ventriculograms from 439 patients with an LVEF >/=0.50 were used to determine LV peak filling rate (PFR) and peak ejection rate (PER) in end-diastolic volumes per second and LV end-systolic volume (ml). Patients with low-normal (n=147; range, 0.50-0.58; mean+/-S.D., 0.53+/-0.02), intermediate-normal (161, 0.59-0.64, 0.61+/-0.02), and high-normal (131, 0.65-0.94, 0.72+/-0.06) LVEF were compared.

RESULTS

From low-normal to intermediate-normal to high-normal LVEF, LV end-systolic volume decreased (93+/-36, 71+/-33, 43+/-26, respectively, P<0.0001), PFR increased (2.31+/-0.74, 2.58+/-0.74, 3.15+/-0.94, P<0.0001), PER increased (-2.78+/-0.50, -3.13+/-0.47, -3.83+/-0.84, P<0.0001), the percentages of patients with abnormal PFR decreased (66, 56, 40, P<.0001), and the percentage with abnormal PER decreased (47, 14, 5, P<0.0001). Of 193 patients with preserved LVEF and abnormally low PFR, 65 (34%) had abnormally low PER.

CONCLUSIONS

The results indicate that a preserved LVEF was often associated with LV systolic dysfunction (enlarged LV end-systolic volume and low PER) and LV diastolic dysfunction (decreased PFR).