Targeting Left Ventricular Mechanics In Patients With Pheochromocytoma/Paraganglioma: An Updated Meta-Analysis

BACKGROUND: Numerous studies targeting left ventricular (LV) systolic function by measuring LV ejection fraction (LVEF) in patients with pheochromocytoma and paraganglioma (PPGL) either failed to reveal any impairment of this parameter or found a super-normal systolic function compared to essential hypertensives or normotensive controls. To provide an updated piece of information on LV systolic dysfunction in the PPGL setting, we performed a meta-analysis of speckle tracking echocardiography (STE) studies investigating LV mechanics via global longitudinal strain (GLS), a more sensitive index of LV systolic function than LVEF. METHODS: A computerized search was performed using PubMed, OVID, EMBASE, and Cochrane library databases from inception until September 30, 2022. Full articles reporting data on LV GLS and LVEF in patients with PPGL and controls were considered suitable. RESULTS: A total of 252 patients with PPGL and 187 controls were included in 6 studies. LV GLS was worse in the pooled PPGL group than in the control group (-17.3 ± 1.2 vs. -20.0 ± 0.6) with a standard means difference (SMD) of 1.13 ± 0.36 confidence interval (CI: 0.43-1.84, P = 0.002), whereas this was not the case for LVEF (67.3 ± 1.9 and 66.4 ± 1.6%, respectively), SMD: 0.12 ± 0.03, (CI: -0.41/0.65, P = 0.66). A meta-regression analysis in PPGL patients showed an inverse relationship between adrenergic activity and GLS (P < 0.0001). CONCLUSIONS: Our findings suggest that early changes in LV systolic function not detectable by conventional echocardiography in the PPGL setting can be revealed by STE; therefore, STE implementation in the workup of patients with PPGL may improve the detection of subclinical systolic dysfunction.