Value of myocardial work for assessment of myocardial adaptation to increased afterload in patients with high blood pressure at peak exercise.

Non-invasive myocardial work (MW) indices are superior to global longitudinal strain (GLS) to assess left ventricular (LV) mechanics in situations where afterload is abnormally high. The rotational motion of the apex provides an accurate index of LV contractility. To date, there are no data about MW values during stress echocardiography (SE), particularly for the apex. Our study aims at assessing MW indices at peak exercise to better understand LV mechanics in patients with high peak systolic blood pressure (SBP). A total of 81 patients without structural or ischemic heart disease referred for SE between January and June 2019 were included. BP measurements, GLS and MW indices were performed at rest and peak exercise. In order to quantify the role of the apex, apical work fraction (AWF) was also calculated and further stratified by peak SBP. A peak SBP > 180 mmHg was considered abnormally high. There were 36 (44%) patients who had peak SBP > 180 mmHg. They showed similar resting GLS and MW values when compared to control. However, peak stress global work index, constructive work and wasted work (GWW) increased significantly (P-value < 0.05), with a relatively constant global work efficiency. In the multivariate analysis, peak SBP > 180 mmHg was associated with threefold increased odds of abnormal peak GWW > 96.5 mmHg% (median value) (odds ratio 3.0, P-value 0.003). Apical work increased significantly when stratified by peak SBP (P-value 0.003) and AWF increased from 33 ± 3% to 37 ± 3% (rest-stress), P-value < 0.0001, but remained constant when stratified by peak SBP. Our analysis provides new data on MW indices at peak stress, particularly for patients with abnormal peak SBP response, and supports the role and the contribution of the apex to MW.

Patients with Isolated Focal Right Ventricular Dyskinetic Segments: Toward a Better Understanding of This Cohort.

BACKGROUND: The 2010 revised Task Force criteria for the diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC) provided guidance for the classification of patients as definitive, borderline or possible ARVC. However, many patients with clinical suspicion for ARVC have isolated RV dyskinetic segments only and partly meet cardiac magnetic resonance (CMR) imaging criteria. This subgroup of patients and the implication of this imaging finding remain not well defined. METHODS: There were 65 consecutive patients with clinical suspicion for ARVC who were referred for CMR between 2015 and 2017. The presence of fatty infiltration and fibrosis were assessed using T2 imaging and myocardial delayed enhancement sequences, respectively. RV wall motions, volumes and ejection fraction (EF) of all patients were re-analysed and quantified. Available data on family history, Holter findings, and electrocardiograms were also reviewed. RESULTS: There were 5 patients (7.7%) that fulfilled major CMR criteria for ARVC: 4 were classified as having definitive ARVC; and 1/5 as borderline. There were 33 patients with no RV dyskinetic segments: none were classified as having definitive or borderline ARVC; 4/33 were classified as possible ARVC, leaving 29/33 as normal or no ARVC. Finally, there were 27 remaining patients (41.5%) with isolated RV dyskinetic segments: 1/27 was classified as definitive ARVC; 4/27 as borderline; 8/27 as possible; leaving 15/27 as indeterminate. Compared to control, those with isolated RV dyskinesia (including the subgroup labelled as indeterminate 15/27) had more abnormal RVEF, larger RV end-diastolic volume index (82 ± 12 mL/m² vs. 72 ± 12 mL/m², p-value 0.0127), and a trend for higher odds of dilated RV (odds ratio 3.0 [0.81-11], p-value 0.09). CONCLUSIONS: Among patients with a clinical suspicion for ARVC, almost 40% had isolated focal RV dyskinetic segments with the majority remaining unclassified. This cohort had more RV dilation and abnormal EF compared to control.