Effect of prespecified therapy escalation on plasma NT-proBNP concentrations in dogs with stable congestive heart failure due to myxomatous mitral valve disease

Radiographic lung congestion scores in dogs with acute congestive heart failure caused by myxomatous mitral valve disease

BACKGROUND

In humans, lung congestion scores are predictive of recurrence of acute congestive heart failure (CHF) and are superior to cardiac biomarkers in predicting survival.

OBJECTIVES

The primary aim of this retrospective study was to determine if a modified lung congestion score (LCS) in dogs diagnosed with acute CHF because of myxomatous mitral valve disease was associated with time until recurrence or death.

ANIMALS

Complete medical records were available for a total of 94 dogs between 2010 and 2019, but only 35 dogs fulfilled the criteria for inclusion.

METHODS

This retrospective study used descriptive statistics to describe the cumulative and corrected LCS. Correlations were used to examine the association of the corrected LCS and time until recurrence or death, selected echocardiographic variables, and timing of furosemide administration.

RESULTS

The mean LCS was 8.4 (SD 3.3) and corrected LCS was 0.48 (SD 0.19). The pattern was predominantly symmetric (40% of dogs) and focal (caudal) but more commonly right-sided when asymmetric (40% vs 20%). The median number of days after initial diagnosis of acute CHF to readmission and death was 150 days (range 4-572), and 266 days (range 5-965), respectively. No significant association between the dog's corrected LCS and number of days until readmission (r = .173, P = .42) nor survival (r = .109, P = .56) was found. There was a negative significant correlation (r = -.71, P < .001) between the time interval of furosemide administration and corrected LCS.

Management of Chronic Congestive Heart Failure Caused by Myxomatous Mitral Valve Disease in Dogs: A Narrative Review from 1970 to 2020

Simple Summary

Myxomatous mitral valve disease (MMVD) is the most common acquired cardiovascular disease in dogs. The progression of the disease and the increasing severity of valvular regurgitation cause a volume overload of the left heart, leading to left atrial and ventricular remodeling and congestive heart failure (CHF). The treatment of chronic CHF secondary to MMVD in dogs has not always been the same over time. In the last fifty years, the drugs utilized have considerably changed, as well as the therapeutic protocols. Some drugs have also changed their intended use. An analysis of the literature concerning the therapy of chronic heart failure in dogs affected by this widespread degenerative disease is not available; a synthesis of the published literature on this topic and a description of its current state of art are needed. To the authors’ knowledge, a review of this topic has never been published in veterinary medicine; therefore, the aim of this study is to overview the treatments of chronic CHF secondary to MMVD in dogs from 1970 to 2020 using the general framework of narrative reviews.

Abstract

The treatment of chronic congestive heart failure (CHF), secondary to myxomatous mitral valve disease (MMVD) in dogs, has considerably changed in the last fifty years. An analysis of the literature concerning the therapy of chronic CHF in dogs affected by MMVD is not available, and it is needed. Narrative reviews (NRs) are aimed at identifying and summarizing what has been previously published, avoiding duplications, and seeking new study areas that have not yet been addressed. The most accessible open-access databases, PubMed, Embase, and Google Scholar, were chosen, and the searching time frame was set in five decades, from 1970 to 2020. The 384 selected studies were classified into categories depending on the aim of the study, the population target, the pathogenesis of MMVD (natural/induced), and the resulting CHF. Over the years, the types of studies have increased considerably in veterinary medicine. In particular, there have been 43 (24.29%) clinical trials, 41 (23.16%) randomized controlled trials, 10 (5.65%) cross-over trials, 40 (22.60%) reviews, 5 (2.82%) comparative studies, 17 (9.60%) case-control studies, 2 (1.13%) cohort studies, 2 (1.13%) experimental studies, 2 (1.13%) questionnaires, 6 (3.40%) case-reports, 7 (3.95%) retrospective studies, and 2 (1.13%) guidelines. The experimental studies on dogs with an induced form of the disease were less numerous (49–27.68%) than the studies on dogs affected by spontaneous MMVD (128–72.32%). The therapy of chronic CHF in dogs has considerably changed in the last fifty years: in the last century, some of the currently prescribed drugs did not exist yet, while others had different indications.

Left ventricular myocardial remodeling in dogs with mitral valve endocardiosis

BACKGROUND AND AIM

Left ventricular myocardial remodeling could play an important role in the progression of chronic heart failure (CHF) syndrome in dogs with mitral valve endocardiosis. The aim of this study was to evaluate the left ventricular myocardial remodeling in dogs with mitral valve endocardiosis and to study the dependence of the incidence of this pathological phenomenon on the functional class (FC) of progression of the CHF syndrome.

MATERIALS AND METHODS

A total of 108 afflicted dogs and 36 clinically healthy dogs were examined using transthoracic echocardiography. The following structural and geometric parameters of the left ventricular remodeling were evaluated: Myocardial mass and its index, sphericity index at the end of systole and diastole, end-systolic and end-diastolic relative wall thickness, and integral remodeling index.

RESULTS

In all clinically healthy dogs, a normal type of the left ventricular chamber geometry was revealed, whereas, in dogs with mitral valve endocardiosis, the normal geometry of the left ventricle occurred in 56.4%, eccentric hypertrophy in 24.1%, concentric remodeling in 10.2%, and concentric hypertrophy in 9.3% of the cases. In patients with endocardiosis, there was no dilatation type of cardiac remodeling observed.

CONCLUSION

When compared to the clinically healthy animals, the dogs with mitral valve endocardiosis presented with indicators of structural and geometric remodeling, such as increased myocardial mass, myocardial mass index, and sphericity index at the end of systole and diastole, as well as relatively reduced integral systolic index of remodeling and systolic relative thickness of the walls of the heart. The parameters of the left ventricular myocardial remodeling correlated significantly with the FC of CHF syndrome.

Effect of prespecified therapy escalation on plasma NT-proBNP concentrations in dogs with stable congestive heart failure due to myxomatous mitral valve disease

Background

Treatment targeted to achieve reduction in N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) improves outcomes in human congestive heart failure (CHF) patients.

Hypothesis

A pre‐specified therapeutic algorithm that increased diuretic or pimobendan usage will reduce plasma NT‐proBNP concentrations in dogs with CHF secondary to myxomatous mitral valve disease (MMVD).

Animals

Twenty‐six dogs with clinically stable CHF secondary to MMVD.

Methods

Prospective, controlled before‐and‐after study. Dogs were examined up to 3 times over 21 days. Treatment was prescribed based on NT‐proBNP as follows: <1500 pmol/L at baseline, no treatment adjustment at any point during the study (group 1); ≥1500 pmol/L and creatinine ≤3.0 mg/dL at baseline or SC visits, treatment escalated according to the algorithm (group 2); ≥1500 pmol/L at baseline, no treatment adjustment (group 3).

Results

N‐terminal pro‐B‐type natriuretic peptide decreased significantly in group 2 (mean change = −1736 pmol/L (95% CI, −804 to −2668), P < .001) but not in groups 1 or 3 (623 pmol/L [–631 to 1877 pmol/L], P = .14 and 685 pmol/L [–304 to 1068 pmol/L], P = .46, respectively). Serum BUN and creatinine did not change significantly between visit 0 and visit 2 in group 1 (median = 23 mg/dL [range 13‐32] versus 19 mg/dL [12‐38], P = .72 and 1.15 mg/dL [0.70‐1.40] versus 0.95 mg/dL [0.70‐1.10], P = .10, respectively) or group 2 (28 mg/dL [18‐87] versus 43.5 mg/dL [21‐160], P = .092 and 1.10 mg/dL [0.90‐2.50] versus 1.55 mg/dL [0.90‐3.30], P = .062, respectively).

Conclusions and Clinical Importance

Use of this treatment escalation algorithm allows effective targeting of treatment for CHF in dogs against an objective criterion.