Modification of ventriculo-arterial coupling by spironolactone in nonischemic dilated cardiomyopathy

Development and Clinical Application of Left Ventricular-Arterial Coupling Non-Invasive Assessment Methods

The constant and dynamic interaction between ventricular function and arterial afterload, known as ventricular-arterial coupling, is key to understanding cardiovascular pathophysiology. Ventricular-arterial coupling has traditionally been assessed invasively as the ratio of effective arterial elastance over end-systolic elastance (Ea/Ees), calculated from information derived from pressure-volume loops. Over the past few decades, numerous invasive and non-invasive simplified methods to estimate the elastance ratio have been developed and applied in clinical investigation and practice. The echocardiographic assessment of left ventricular Ea/Ees, as proposed by Chen and colleagues, is the most widely used method, but novel echocardiographic approaches for ventricular-arterial evaluation such as left ventricle outflow acceleration, pulse-wave velocity, and the global longitudinal strain or global work index have arisen since the former was first published. Moreover, multimodal imaging or artificial intelligence also seems to be useful in this matter. This review depicts the progressive development of these methods along with their academic and clinical application. The left ventricular-arterial coupling assessment may help both identify patients at risk and tailor specific pharmacological or interventional treatments.

Cardiac reverse remodelling by imaging parameters with recent changes to guideline medical therapy in heart failure

Recently established heart failure therapies, including sodium glucose co-transporter 2 inhibitors, angiotensin-neprilysin inhibitors, and cardiac resynchronization therapy, have led to both clinical and structural improvements. Reverse remodelling describes the structural and functional responses to therapy and has been shown to correlate with patients' clinical response, acting as a biomarker for treatment success. The introduction of these new therapeutic agents in addition to advances in non-invasive cardiac imaging has led to an expansion in the evaluation and the validation of cardiac reverse remodelling. Methods including volumetric changes as well as strain and myocardial work have all been shown to be non-invasive end-points of reverse remodelling, correlating with clinical outcomes. Our review summarizes the current available evidence on reverse remodelling in heart failure by the non-invasive cardiac imaging techniques, in particular transthoracic echocardiography.

Evaluation of the pharmacotherapeutic impact on contractility recovery in patients with newly diagnosed, acute onset dilated cardiomyopathy

In patients with acute onset dilated cardiomyopathy (DCM) an improvement of left ventricular ejection fraction (LVEF) can occur as an effect of complex therapy. The aim of the study was to evaluate a pharmacotherapeutic impact on LVEF recovery in newly diagnosed DCM heart failure (HF) patients. A total of 2436 patients hospitalized due to acute decompensated HF were retrospectively analyzed. Finally, 24 patients with newly diagnosed DCM (51.4 ± 16.3 years, New York Heart Association 2.3 ± 0.7, LVEF 25 ± 10%) were observed (13.4 ± 16.0 months) in terms of the result of complex therapy. Patients were divided according to LVEF improvement on follow-up echocardiography: "recovery group" (LVEF improvement > 5%; n = 13) and "nonrecovery group" (∆LVEF ≤ 5%; n = 11). Evaluation of baseline parameters showed lower LVEF (19 ± 6 vs 31 ± 10%; P = .0048) and lower incidence of arterial hypertension (27% vs 73%; P = .043) in "recovery" group. After follow-up period LVEF was similar in both groups; however, significant LVEF improvement was demonstrated only in the "recovery group" (19 ± 6% to 34 ± 8%; P < .001). Only the "recovery group" showed significant HF symptoms reduction (New York Heart Association class: 2.5 ± 0.7 to 1.6 ± 0.6; P = .003). The "recovery group" had prescribed higher doses of loop diuretic (equivalent dose of furosemidum: 80 ± 38 mg vs 43 ± 24 mg; P = .025). Despite optimal therapy, significant LVEF improvement is observed only in the half of the patients with newly diagnosed DCM with HF with reduced EF. Prescription of higher doses of loop diuretics may have positive effect on the reduction of symptoms in newly diagnosed DCM HF patients. Lack of other risk factors such as arterial hypertension may increase the chance of LVEF recovery.

Effect of nitroglycerin on splanchnic and pulmonary blood volume

BACKGROUND

Sublingual nitroglycerin (SL NTG) is useful for treating acute decompensated heart failure, possibly by increasing splanchnic capacitance and reducing left ventricular (LV) preload. We evaluated a radionuclide method to study these effects, initially in subjects without heart failure.

METHODS AND RESULTS

Red blood cells were labelled by an in vitro method. Abdominal and chest images were obtained at rest, showing relative regional blood volumes. The abdomen was then re-imaged during progressive escalation of intrathoracic pressure using continuous positive airway pressure to assess baseline splanchnic capacitance (pressure-volume relationship, PVR) and compliance (slope of PVR). The procedure was repeated after 0.6 mg SL NTG, followed by chest images. Relative splanchnic blood volume increased at rest after SL NTG (P < .002), signifying an increase in splanchnic capacitance. The slope of the splanchnic PVR decreased in proportion to the baseline PVR (P = .0014), signifying increased compliance. The relative pulmonary blood volume decreased in proportion to the increase in splanchnic blood volume (P = .01).

CONCLUSIONS

A semi-quantitative radionuclide method demonstrated the effect of SL NTG for increasing splanchnic capacitance and compliance, with a proportional decrease in pulmonary blood volume. These data may be applied to quantitatively evaluate the importance of splanchnic vasodilation as a mechanism of LV preload reduction in the treatment of heart failure.

CLINICAL TRIALS REGISTRATION

NCT02425566.

Modification of ventriculo-arterial coupling by spironolactone in nonischemic dilated cardiomyopathy

Aims

We sought to clarify the role of ventriculo–arterial (V–A) coupling in the treatment of nonischemic dilated cardiomyopathy (NIDCM) by adding a mineralocorticoid receptor antagonist (MRA) to conventional anti‐failure therapy.

Methods and results

We employed cardiac magnetic resonance imaging to quantify left ventricular (LV) contractility and V–A coupling in normal subjects at rest (n = 11) and in patients with NIDCM (n = 12) before and after long term anti‐failure therapy, in which MRA was added to conventional anti‐failure therapy. After ≥6 months' treatment in NIDCM patients, LV volumes and mass decreased, and the LV ejection fraction increased from a median of 24% (17, 27) (interquartile range IQR) to 47 (42, 52) (P < 0.002), with a marked reduction in arterial elastance (Ea) from 2.89 mmHg/mL (2.34, 4.0) to 1.50 (1.29, 1.95) (P < 0.002), similar to Ea of normal subjects, 1.53 (1.34, 1.67) (P > 0.05). The V–A coupling ratio, Ea/end‐systolic elastance (single‐beat method), decreased by −1.08 (−1.96, −0.55), (P = 0.003), as did Ea/end‐systolic pressure/end‐systolic pressure ratio, −0.54 (0.35, 0.87), (P = 0.002). The preload recruitable stroke work (PRSW) increased as did PRSW indexed for Ea (both P = 0.002), which reflected ‘total circulatory performance’.

Conclusions

In NIDCM, adding MRA to conventional anti‐failure therapy markedly improved LV ejection fraction and reduced peripheral vascular resistance, due to both improved LV contractility and especially to enhanced V–A coupling, as Ea decreased to normal. Total circulatory performance was a sensitive indicator of both LV pump performance and the arterial loading conditions.