Partial vena cava occlusion (VCO) to counteract refractory heart failure: A new era in interventional heart failure strategy

Background

Patients with acute decompensated heart failure are prone to recurrent exacerbation leading to poor quality of life when they do not respond to an optimal medical regimen. Due to the lack of linear positive inotropy response to increasing preload in heart failure patients, increasing preload is associated with poor outcomes. Partial occlusion of either IVC or SVC is a proposed novel treatment that can improve cardiac function or quality of life by altering preload/pressure in heart failure (HF) patients unresponsive to diuretics.

Methods

PubMed, Ovid (MEDLINE), and Cochrane database we searched using the MeSH terms including “Superior vena cava occlusion,” “Inferior vena cava occlusion,” “Heart failure exacerbation.” The inclusion criteria included studies that enrolled patients > 18 years with diagnosed NYHA II-IV HF with reduced ejection fraction (HFrEF) on optimal medical treatment (OMT).

Results

The analysis involved two studies with 14 patients; the mean age was 64.4 ± 10 and 100% males. The difference in the mean pulmonary pressures between pre-and-post VCO devices were 1.56 (95% CI 0.66–2.46, p-value = 0.006). There was no heterogeneity among the study of mean pulmonary pressures. With the use of VC occlusion devices, the mean difference in pulmonary artery systolic pressure decreased by 1.70 (95% CI 0.68–2.71, p-value = 0.001) (Fig. 1B). The heterogeneity of mean pressure was minimal 14%.

Conclusion

In conclusion, VCO can help decrease pulmonary pressure that can indirectly prevent heart failure exacerbations and possibly hospitalization in this cohort of patients.

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Patients with acute decompensated heart failure are prone to recurrent exacerbation when they do not respond to an optimal medical regimen.

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Partial occlusion of either IVC or SVC is a proposed novel treatment that can improve cardiac function or quality of life by altering preload/pressure in heart failure (HF) patients.

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The choice of vena cava for device implantation is also essential. However, it is not well discussed in the literature.

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This meta-analysis aims to bridge the gap in literature that precludes the uptake of partial VCO as a routine treatment modality for refractory heart failure.

Effect of preload reducing therapy on right ventricular size and function in patients with arrhythmogenic right ventricular cardiomyopathy

BACKGROUND

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an important cause of sudden cardiac death in young people and athletes. To date, no treatment has proven to slow the progression of the disease. Preload reducing agents such as nitrates and diuretics have shown promising results in preventing training-induced development of ARVC in a murine model.

OBJECTIVE

The purpose of this study was to describe our experience with preload reducing therapy in patients with ARVC and symptomatic right ventricular (RV) dysfunction.

METHODS

We performed retrospective chart review of prospectively collected registry data and included 20 patients with definite ARVC who had serial echocardiographic measurements and an implantable cardioverter-defibrillator. Six of the 20 patients with RV end-diastolic area (RVEDA) above median (>25 cm²) and New York Heart Association functional class II-IV symptoms were successfully treated with long-term isosorbide dinitrate 5-40 mg tid (at maximum tolerated dose) and hydrochlorothiazide-spironolactone 25-25 mg daily. The main outcomes of interest were RVEDA, RV fractional area change (FAC), and RV outflow tract measurements. Generalized estimating equations with repeated measures were used to identify the association between preload reducing agents and echocardiographic structural progression.

RESULTS

Patients who received preload reducing agents (n = 6) were older and had larger RVs with lower FAC at baseline. However, treatment with preload reducing agents was associated with less RVEDA enlargement during mean 3.3 (range 1-6.7) years of treatment in multivariate analysis (% change in RVEDA associated with treatment -7.71; 95% confidence interval -13.29 to -2.13; P = .007).

CONCLUSION

Preload reducing agents show promising results in slowing RV enlargement in patients with ARVC and show possible disease-modifying potential.

The design and use of a simple device for the MRI assessment of changes in cardiovascular function by lower-body negative-pressure-simulated reduction of central blood volume

AIM

To use a locally designed and simple lower-body negative-pressure (LBNP) device and 1.5 T magnetic resonance imaging (MRI) to demonstrate the ability to assess changes in cardiovascular function during preload reduction. These effects were evaluated on ventricular volumes and great vessel flow in healthy volunteers, for which there are limited published data.

MATERIAL AND METHODS

After ethical review, 14 volunteers (mean age 33.9 ± 7 years, mean body mass index [BMI] 23.1 ± 2.5) underwent LBNP prospectively at 0, -5, -10, and -20 mmHg pressure, using a locally designed LBNP box. Expiratory breath-hold biventricular volumes, and free-breathing flow imaging of the ascending aorta and main pulmonary artery were acquired at each level of LBNP.

RESULTS

At -5 mmHg, there was no change in aortic flow or left ventricular volumes versus baseline. Right ventricular output (p=0.013) and pulmonary net flow (p=0.026) decreased. At -20 mmHg, aortic and pulmonary net flow (p<0.001) decreased, as were left and right ventricular end diastolic volume (p<0.001) and left and right end systolic volumes (p=0.038 and p=0.003 respectively).

CONCLUSIONS

Use of a MRI-compatible LBNP device is feasible to measure changes in ventricular volume and great arterial flow in the same experiment. This may enhance further research into the effects of preload reduction by MRI in a wide range of important cardiovascular pathologies.