How is the peri-patch myocardium in ventricular septal defect patch repair?

Abstract

Strain rate (SR) and strain (≈) in tissue Doppler imaging provide new noninvasive measurements of myocardial function, independent of heart motion. This study assesses the extent of peri-patch regional myocardial function after patch repair of ventricular septal defect (VSD). Myocardial SR and ≈ were recorded from the peri-patch myocardium and remote septum from patch area in 18 patients (1 month to 4 years of age, mean 2.3 years). Distance between the patch and the point of returning to remote normal strain (≈) profile was measured. Compared to the remote myocardial region, peri-patch myocardium had decreased peak longitudinal SR (-3.8 ± 2.1s(-1) vs. -5.3 ± 3.3s(-1), p<0.05), delayed time to peak longitudinal SR (144 ± 59 ms vs. 110 ± 46 ms, p<0.05), decreased peak ≈ (longitudinal, -20.8 ± 8.1% vs. -28.7 ± 11.1%; radial, 20.1 ± 16.3% vs. 34.3 ± 22.4%, p<0.01), and delayed time to peak ≈ (longitudinal, 314 ± 80 ms vs. 241 ± 63 ms; radial, 329 ± 99 ms vs. 265 ± 78 ms, p<0.0001). The mean distance from the patch to the remote patch ɛ curve was 2.55 ± 0.77 mm.

Conclusion: Peri-patch myocardium after repair of VSD has delayed and diminished contraction as compared to more remote normal myocardium.