Background-Diastolic strain rate (SR) measurements that comprise all left ventricular (LV) segments are advantageous over myocardial velocity for assessment of diastolic function. Mitral early diastolic velocity (E)/SR ratio during the isovolumetric relaxation (IVR) period can be used to estimate LV filling pressures. Methods and Results-Simultaneous echocardiographic imaging and LV pressure measurements (7F catheters) were performed in 7 adult dogs. Loading conditions were altered by saline infusion and caval occlusion, and lusitropic state was changed by dobutamine and esmolol infusion. A curve depicting global SR was derived from each of the 3 apical views, and SR was measured during IVR (SR IVR ) and early LV filling (SR E ). SR IVR had a strong correlation with time constant of LV pressure decay during the IVR period () (rϭϪ0.83, PϽ0.001), whereas SR E was significantly related to LV end-diastolic pressure (rϭ0.52, Pϭ0.005) in the experimental stages where was Ͻ40 ms. In 50 patients with simultaneous right heart catheterization and echocardiographic imaging, mitral E/SR IVR ratio had the best correlation with mean wedge pressure (rϭ0.79, PϽ0.001), as well as in 24 prospective patients (rϭ0.84, Pϭ0.001). E/SR IVR was most useful in patients with ratio of E to mitral annulus early diastolic velocity (E/Ea ratio) 8 to 15 and was more accurate than E/Ea in patients with normal ejection fraction and regional dysfunction (both PϽ0.01). Conclusions-Global SR IVR by 2-dimensional speckle tracking is strongly dependent on LV relaxation. E/SR IVR can predict LV filling pressures with reasonable accuracy, particularly in patients with normal ejection fraction and in those with regional dysfunction.

BACKGROUND Peripartum cardiomyopathy shares some clinical features with idiopathic dilated cardiomyopathy, a disorder caused by mutations in more than 40 genes, including TTN, which encodes the sarcomere protein titin. METHODS In 172 women with peripartum cardiomyopathy, we sequenced 43 genes with variants that have been associated with dilated cardiomyopathy. We compared the prevalence of different variant types (nonsense, frameshift, and splicing) in these women with the prevalence of such variants in persons with dilated cardiomyopathy and with population controls. RESULTS We identified 26 distinct, rare truncating variants in eight genes among women with peripartum cardiomyopathy. The prevalence of truncating variants (26 in 172 [15%]) was significantly higher than that in a reference population of 60,706 persons (4.7%, P = 1.3×10−7) but was similar to that in a cohort of patients with dilated cardiomyopathy (55 of 332 patients [17%], P = 0.81). Two thirds of identified truncating variants were in TTN, as seen in 10% of the patients and in 1.4% of the reference population (P = 2.7×10−10); almost all TTN variants were located in the titin A-band. Seven of the TTN truncating variants were previously reported in patients with idiopathic dilated cardiomyopathy. In a clinically well-characterized cohort of 83 women with peripartum cardiomyopathy, the presence of TTN truncating variants was significantly correlated with a lower ejection fraction at 1-year follow-up (P = 0.005). CONCLUSIONS The distribution of truncating variants in a large series of women with peripartum cardiomyopathy was remarkably similar to that found in patients with idiopathic dilated cardiomyopathy. TTN truncating variants were the most prevalent genetic predisposition in each disorder.

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Objective To determine if low to moderate doses of anthracycline-based chemotherapy (Anth-bC) are associated with subclinical cardiovascular (CV) injury. Background Cancer survivors that receive Anth-bC experience premature CV events. It is unknown whether low to moderate doses of anthracyclines a) promote early subclinical CV disease manifested by deteriorations in left ventricular ejection fraction (LVEF) or increases in aortic stiffness, or b) are associated with change in quality of life (QOL). Methods In 53 men and women with breast cancer, leukemia, or lymphoma, we assessed left ventricular volumes, LVEF, circumferential strain, aortic pulse wave velocity (PWV), late gadolinium enhancement, serum B-type natriuretic peptide (BNP), troponin I (TnI), and the impact of treatment on QOL before, and 1, 3, and 6 months after receipt of Anth-bC. Results Participants averaged 50±2 (range 19–80) years in age, 58% were women, 17% were black, and they each received a range of 50 to 375 mg/m2 of doxorubicin equivalent chemotherapy. Left ventricular end systolic volume (LVESV; 48±3 to 54±3 ml; p=0.02), left ventricular strain (−17.7±0.4 to −15.1±0.4; p=0.0003), PWV (6.7±0.5 to 10.1±1 m/sec; p=0.0006), and QOL deterioration (15.4±3.3 to 28.5±3.9; p=0.008) increased, while LVEF (58±1 to 53±1%; p=0.0002) decreased within 6 months after low to moderate doses of Anth-bC. All findings persisted after accounting for age, gender, race (white/black), doxorubicin equivalent dose, doxorubicin administration technique, comorbidities associated with CV events, and cancer diagnosis (p=0.02 to 0.0001 for all). There were no new late gadolinium enhancement findings after 6 months. Conclusions Low to moderate doses of Anth-bC are associated with the early development of subclinical abnormalities of cardiac and vascular function that in other populations are associated with the future occurrence of CV events.

(N Engl J Med. 2016;374:233–241) It is possible that peripartum cardiomyopathy is influenced by genetic factors, though this remains unclear. Similar to idiopathic dilated cardiomyopathy, this disease is associated with decreased systolic function, enlarged cardiac dimensions, and nonspecific histologic findings. These similarities are significant in that idiopathic dilated cardiomyopathy has been shown to be caused by a number of gene mutations. The authors of this study sequenced the DNA of 172 women suffering from peripartum cardiomyopathy to investigate whether there was a contribution from variants in the 43 genes known to be associated with dilated cardiomyopathy.