Heart rate monitoring can predict DCMP relapse after treatment withdrawal, JACC study.

Following recovery of left ventricle (LV) systolic function in cases of dilated cardiomyopathy (DCMP), it remains unclear whether to stop the heart failure medications or to continue them for indefinite period. According to the results from a study by Halliday et al, published in JACC Heart Failure, a rise in heart rate is associated with adverse remodeling and relapse among patients with recovered dilated cardiomyopathy whose medication is withdrawn. This can thus serve as a marker to predict relapse of DCMP in patients seeking the option of therapy withdrawal.

There are no reliable predictors to identify patients who will relapse after therapy is withdrawn. Therefore, patients with DCMP whose ventricular function has improved are typically advised to remain taking disease-modifying treatments for heart failure lifelong. However, such a blanket approach may not be considered prudent for different etiologies of DCMP many of which are reversible and correctable. For example, a patient of peripartum cardiomyopathy (PPCM), post recovery of ejection fraction (EF) may wish to stop ACE-inhibitor therapy while planning to conceive again.

The best way to monitor withdrawal or reduction of therapy to predict and prevent relapse is unknown. A strong association among achieved heart rate, temporal changes in heart rate, and outcome among patients with heart failure is well established. In the present study, the associations among change in heart rate and attained heart rate and the occurrence of relapse among patients in the TRED-HF trial (a randomized trial which examined the safety and feasibility of withdrawing heart failure therapy from 51 patients with recovered DCMP over 6 months) was examined.

In total, 25 patients were randomized to therapy withdrawal and 26 to continue therapy, of whom 25 subsequently began therapy withdrawal in a single arm crossover phase. The primary endpoint was a relapse of DCMP defined by any 1 of the following: 1) a reduction in LVEF by >10% and to 10% and to above the normal range; or 3) a two-fold rise in NT-proBNP from baseline and to >400 ng/l; or 4) clinical evidence of heart failure.

The study showed that:

1. Heart rate and change in heart rate from baseline are associated with relapse among patients with recovered DCMP who had therapy withdrawn.

2. Maintaining a lower heart rate was associated with a lower risk of relapse.

3. Patients who did not relapse after having therapy withdrawn had an average rise in heart rate of 10 beats/min compared to 18 beats/min for those patients who relapsed.

4. After adjusting for differences in heart rate at baseline, the average rise in heart rate among patients who met the primary endpoint was 10 beats/min greater than those who did not relapse.

5. This intergroup difference in heart rates was evident as early as 8 weeks of therapy withdrawal.

6. The results remained qualitatively the same after adjusting for beta-blocker dose.

Thus, for patients with DCMP and improved LVEF, the rise in heart rate after treatment is withdrawn identifies patients who are more likely to relapse. Whether the increase in heart rate is a marker or a mediator of relapse requires investigation because an increase in heart rate was evident after withdrawing both heart rate lowering (beta-blocker) and other medications (ACE-inhibitors, diuretics, etc.)

Nevertheless, based on these data, a heart rate rise of >10 beats/min from baseline may act as a prompt for expedited imaging investigation like cardiac MRI to detect relapse after treatment withdrawal in DCMP patients. This approach may be suitable for most reversible etiologies of DCMP like myocarditis sequel, PPCM, tachycardia induced cardiomyopathy, etc once the underlying cause is corrected.

Source: JACC Heart Failure: https://doi.org/10.1016/j.jchf.2021.03.010