Association between myocardial work indices and cardiovascular events according to hypertension in the general population

AIMS

Pressure-strain loop (PSL) analysis is a novel echocardiographic tool capable of assessing myocardial work non-invasively. In this study, we aim to evaluate the prognostic value of myocardial work indices in the general population.

METHODS AND RESULTS

This was a prospective community-based cohort study (n = 4466). PSL analyses were performed to acquire global work index (GWI), global constructive work (GCW), global wasted work, and global work efficiency (GWE). The endpoint was a composite of heart failure or cardiovascular death (HF/CVD). Survival analysis was applied. A total of 3932 participants were included in this analysis (median age: 58 years, 43% men). Of these, 124 (3%) experienced the outcome during a median follow-up period of 3.5 years [interquartile range (IQR): 2.6-4.4 years]. Hypertension significantly modified the association between all work indices and outcome (P for interaction < 0.05), such that work indices posed a higher risk of outcome in non-hypertensive than in hypertensive participants. After adjusting for Atherosclerosis Risk in Communities (ARIC)-HF risk variables, all work indices predicted outcome in non-hypertensive participants, but only GWI, GCW, and GWE predicted outcome in hypertensive participants [GWI: hazard ratio (HR) = 1.12 (1.07-1.16), per 100 mmHg% decrease; GCW: HR = 1.12 (1.08-1.17), per 100 mmHg% decrease; GWE: HR = 1.08 (1.04-1.12), per 1% decrease]. Only GWE significantly increased C-statistics when added to ARIC-HF risk variables in hypertensive participants (C-stat 0.865 vs. 0.877, P for increment = 0.003).

CONCLUSION

Hypertension modifies the association between myocardial work indices and HF/CVD in the general population. All work indices are associated with outcome in normotensive participants. GWI, GCW, and GWE are independently associated with outcome in hypertension, but only GWE improves risk prediction.

Interplay between natriuretic peptides and left atrial mechanics and the relation to recurrence of atrial fibrillation following catheter ablation

The relationship between natriuretic peptides and atrial distension is not fully understood. We sought to examine their interrelationship and how they relate to atrial fibrillation (AF) recurrence following catheter ablation. We analyzed patients enrolled in the AMIO-CAT trial (amiodarone vs. placebo for reducing AF recurrence). Echocardiography and natriuretic peptides were assessed at baseline. Natriuretic peptides included mid-regional proANP (MR-proANP) and N-terminal proBNP (NT-proBNP). Atrial distension was assessed by left atrial strain measured by echocardiography. The endpoint was AF recurrence within 6 months after a 3-month blanking period. Logistic regression was used to assess the association between log-transformed natriuretic peptides and AF. Multivariable adjustments were made for age, gender, randomization, and left ventricular ejection fraction. Of 99 patients, 44 developed AF recurrence. No differences in natriuretic peptides nor echocardiography were observed between the outcome groups. In unadjusted analyses, neither MR-proANP nor NT-proBNP were significantly associated with AF recurrence [MR-proANP: OR = 1.06 (0.99-1.14), per 10% increase; NT-proBNP: OR = 1.01 (0.98-1.05), per 10% increase]. These findings were consistent after multivariable adjustments. However, atrial strain significantly modified the association between MR-proANP and AF (p for interaction = 0.009) such that MR-proANP was associated with AF in patients with high atrial strain [OR = 1.24 (1.06-1.46), p = 0.008, per 10% increase] but not in patients with low atrial strain. In patients with high atrial strain, an MR-proANP > 116 pmol/L posed a fivefold higher risk of AF recurrence [HR = 5.38 (2.19-13.22)]. Atrial natriuretic peptide predicts AF recurrence in patients with preserved atrial distension. Assessing atrial strain may assist the interpretation of natriuretic peptides.