Prognostic utility of left ventricular global longitudinal strain in patients with systemic amyloidosis

Background

Myocardial deposition of amyloid proteins results in restrictive cardiomyopathy. Left ventricular global longitudinal strain (GLS) has emerged as a sensitive measure for detecting subclinical cardiac dysfunction over traditional echocardiographic parameters. However, multiple studies have provided differing conclusions regarding prognostic utility of impaired GLS in patients with systemic amyloidosis.

Purpose

We conducted a systematic review and meta-analysis to evaluate whether impaired GLS was associated with increased mortality or major adverse cardiovascular events (MACE) in patients with systemic amyloidosis.

Methods

We performed a literature search of Embase, Medline and Web of Science databases to identify studies that reported the association of GLS with clinical outcomes in patients with systemic amyloidosis (light chain or TTR amyloidosis). Outcomes of interest included all-cause mortality and MACE, defined as a composite of death or heart transplant or heart failure hospitalization. Unadjusted and adjusted hazard ratio (uHR and aHR respectively) were pooled using a random effects model. Heterogeneity among the studies was assessed using the Higgins I2 value.

Results

Out of 2139 initial citations, 28 observational studies with a total of 2713 patients were included in the analysis. The mean age ranged between 58–78 years and 62% of the patients were male. Most patients had cardiac amyloidosis (83%) and light-chain amyloidosis accounted for 69% of cases. Mean follow-up ranged between 1 and 5 years. GLS was significantly higher (less negative) (mean difference (MD) −3.69 [−5.94, −1.44], I2=87, p<0.01) in non-survivors compared with survivors. Similarly, patients who experienced MACE had a significantly higher mean GLS (MD −3.22, [−5.21, −1.22,], I2=82, p<0.01]. The risk of both mortality and MACE increased significantly for every −1% increase in GLS. In unadjusted models, a GLS above the defined threshold value was associated with a significantly higher risk of mortality (uHR: 1.66 [1.22, 5.21], I2=85.2, p<0.01) and MACE (uHR: 2.24 [1.28, 3.92], I2=39, p<0.01). In multivariable models an increase in GLS by −1% was an independent predictor of mortality (aHR: 1.09 [1.01,1.16], I2=53, p=0.02) and MACE (aHR: 1.24 [1.14,1.36], I2=0, p<0.01).

Conclusion

In patient with amyloidosis, the baseline left ventricular GLS may help identify patients with a higher risk of mortality and MACE.

Funding Acknowledgement

Type of funding sources: None.

6067Right ventricular global longitudinal strain predicts cardiovascular mortality and heart failure hospitalization in patients with functional tricuspid regurgitation

Background

Functional tricuspid regurgitation (FTR) and its increasing severity are well-known factors associated with increased morbidity and mortality in patients with pulmonary artery hypertension or left heart diseases.

Purpose

To assess the main clinical and echocardiographic determinants of outcome in patients with various causes of FTR.

Methods

A total of 140 patients (pts) (72±14 years, 40% men) with FTR of diverse etiologies underwent complete 2D and additional 3D echocardiography acquisitions and were followed for a median of 5.2 years (interquartile range 2.1 - 6.7 years). Severe FTR was defined by ≥2 parameters: (1) coaptation defect; (2) vena contract ≥7; (3) PISA radius >9 mm; (4) hepatic vein systolic flow reversal. The primary composite outcome was defined as death from cardiovascular causes and hospitalization due to right-sided heart failure (HF).

Results

74 pts (53%) developed the primary composite outcome. Death occurred in 31 pts (22%), while hospitalization due to right-sided HF occurred in 66 pts (47%). At baseline, patients who developed the primary composite outcome, compared to those who did not, had more symptoms, more severe FTR, higher pulmonary systolic pressure (60±27 vs 43±16 mmHg), larger right atrium (69±34 vs 51±22 mL/mm2), right ventricular (RV) basal diameter (29±6 vs 24±4 mm/m2), larger RV end-diastolic (102±45 vs 76±25 mL/m2) and end-systolic (62±37 vs 43±17 mL/m2) volumes, larger tricuspid annulus area (7.7±1.8 vs 6.8±1.8 cm2/m2), lower RV systolic function (RVEF [42±11 vs 46±8%], TAPSE [18±4 vs 21±4], S' [11±3 vs 12±2], RV global longitudinal strain (RVGLS) [16±5 vs 19±4], RV free wall longitudinal strain [19±7 vs 23.5]); all p-values <0.03. There were no significant differences in age, body size or comorbidities. After multivariable Cox regression analysis, FTR grade severity (hazard ratio [HR]=2.95, 95% confidence interval [CI] 2.14–4.06, p<0.001) and RVGLS (HR= 0.91, 95% CI 0.86–0.95) were the only independent predictors of mortality. A cutoff of −17.5 for RVGLS had 57% sensitivity, 73% specificity and a HR of 2.34 (95% CI of 1.42–3.88, p-value=0.001). The Kaplan Meier survival curve showed that patients with an RVGLS ≥ −17.5 had a higher probability of developing the primary composite outcome, especially at an earlier phase of the follow up when compared to those with higher LS (log rank test chi-square = 13.0, p<0.001) (Figure). At the end of follow up, 60% of patients with a RVGLS ≥-17.5 did not developed the primary composite outcome vs 29% in the group with a LS lower than −17.5.

Kaplan-Meier curve of outcome by RVGLS

Conclusions

In patients with FTR, a decreased RVGLS, with a cutoff of −17.5, proved to be an independent prognostic factor for the development of HF hospitalizations and death from cardiovascular causes.