Improvement of cardiac function and neurological remodeling in a patient with tachycardia-induced cardiomyopathy after catheter ablation

Long-Term Outcomes of Tachycardia-Induced Cardiomyopathy Compared with Idiopathic Dilated Cardiomyopathy

BACKGROUND

data on the natural course and prognosis of tachycardia-induced cardiomyopathy (TICMP) and comparison with idiopathic dilated cardiomyopathies (IDCM) are scarce.

OBJECTIVE

To compare the clinical presentation, comorbidities, and long-term outcomes of TICMP patients with IDCM patients.

METHODS

a retrospective cohort study of patients hospitalized with new-onset TICMP or IDCM. The primary endpoint was a composite of death, myocardial infarction, thromboembolic events, assist device, heart transplantation, and ventricular tachycardia or fibrillation (VT/VF). The secondary endpoint was recurrent hospitalization due to heart failure (HF) exacerbation.

RESULTS

the cohort was comprised of 64 TICMP and 66 IDCM patients. The primary composite endpoint and all-cause mortality were similar between the groups during a median follow-up of ~6 years (36% versus 29%, p = 0.33 and 22% versus 15%, p = 0.15, respectively). Survival analysis showed no significant difference between TICMP and IDCM groups for the composite endpoint (p = 0.75), all-cause mortality (p = 0.65), and hospitalizations due to heart failure exacerbation. Nonetheless, the incidence of recurrent hospitalization was significantly higher in TICMP patients (incidence rate ratio 1.59; p = 0.009).

CONCLUSIONS

patients with TICMP have similar long-term outcomes as those with IDCM. However, it portends a higher rate of HF readmissions, mostly due to arrhythmia recurrences.

A case of successful catheter ablation of blocked atrial bigeminy and bradycardia with the recovery of normal sinus rhythm and myocardial reverse remodeling

A 69-year-old man presented bradycardia with a constant blocked atrial bigeminy and heart failure. Successful catheter ablation of blocked atrial bigeminy with bradycardia resulted in myocardial reverse remodeling and restoration of the normal sinus rhythm from the ectopic atrial rhythm.

What About Tachycardia-induced Cardiomyopathy?

Long-standing tachycardia is a well-recognised cause of heart failure and left ventricular dysfunction, and has led to the nomenclature, tachycardia-induced cardiomyopathy (TIC). TIC is generally a reversible cardiomyopathy if the causative tachycardia can be treated effectively, either with medications, surgery or catheter ablation. The diagnosis is usually made after demonstrating recovery of left ventricular function with normalisation of heart rate in the absence of other identifiable aetiologies. One hundred years after the first reported case of TIC, our understanding of the pathophysiology of TIC in humans remains limited despite extensive work in animal models of TIC. In this review we will discuss the proposed mechanisms of TIC, the causative tachyarrhythmias and their treatment, outcomes for patients diagnosed with TIC, and future directions for research and clinical care.

Radiofrequency ablation can reverse the structural remodeling caused by frequent premature ventricular contractions originating from the right ventricular outflow tract even in a "normal heart"

OBJECTIVE

The aim of this study was to evaluate whether frequent premature ventricular contractions originating from the right ventricular outflow tract remodel the cardiac structure and function in patients with a "seemingly normal heart" and whether radiofrequency ablation can reverse this remodeling.

METHODS

Sixty-eight patients with idiopathic frequent premature ventricular contractions originating from the right ventricular outflow tract and normal heart structure and function were enrolled in this study. The patients were divided into three groups according to the therapeutic method: radiofrequency ablation group (24 cases), anti-arrhythmia drug group (26 cases), and control group (18 cases without any treatment). Clinical Registration number: ChiCTR-ONRC-12002834 RESULTS: The basic patient characteristics were comparable between the three groups, except for the premature ventricular contraction rate, which was significantly lower in the control group. After six months of follow up, the premature ventricular contraction rate was significantly reduced in the radiofrequency ablation group, which was accompanied by a significant decrease in the following cardiac cavity inner diameters, as determined by echocardiography: right atrium (33.33±3.78 vs. 30.05±2.60 mm, p = 0.001), right ventricle (23.24±2.40 vs. 21.05±2.16 mm, p = 0.020), and left ventricle (44.76±4.33 vs. 41.71±3.44 mm, p = 0.025). These results were similar in the anti-arrhythmia drug group, although this group exhibited a smaller extent of change (right atrium: 33.94±3.25 vs. 31.27±3.11 mm, p = 0.024; right ventricle: 22.97±3.09 vs. 21.64±2.33 mm, p = 0.049; left ventricle: 45.92±6.38 vs. 43.84±5.67 mm, p = 0.039), but not in the control group (p>0.05). There was a tendency toward improvement in the cardiac functions in both the radiofrequency ablation and anti-arrhythmia drug groups. However, these differences were not statistically significant (p>0.05).

CONCLUSIONS

These results indicate that radiofrequency ablation can potentially reverse the cardiac remodeling caused by frequent premature ventricular contractions even in structurally normal hearts and that frequent premature ventricular contractions should be abated even in structurally normal hearts.

Reversible cardiomyopathies--a review

End-stage renal disease, cirrhosis, obesity, tachycardia, and extreme stress have all been shown to result in impaired left ventricular function. It is becoming clear, however, that the cardiomyopathies associated with these states are reversible after resolution of the underlying process. In this article, we present the current data demonstrating that renal transplantation, liver transplantation, and bariatric surgery can lead to reversal of uremic, cirrhotic, and obesity cardiomyopathies, respectively. We also discuss the reversibility of tachycardia-induced cardiomyopathy after radiofrequency ablation or pharmacologic therapy for rate or rhythm control and the reversibility of stress-induced cardiomyopathy with supportive care.

Ventricular tachyarrhythmia-related basal cardiomyopathy in rabbits with vagal stimulation--a novel experimental model for inverted Takotsubo-like cardiomyopathy

BACKGROUND

Electrical stimulation of the intact (unsectioned) cervical vagus in rabbits frequently provokes ventricular tachyarrhythmias that are often accompanied by mitral regurgitation. Unique pathological lesions often arise on the mitral valve, papillary muscles, and mitral annulus (mitral complex), the latter two of which become swollen and stiffened. These lesions are reversible in nature. Previous studies have essentially ignored the basal portion except for the mitral annulus. Therefore, the present study examined pathological lesions on the left ventricular basal portion in rabbits.

METHODS

The intact right vagal nerves of 20 anesthetized rabbits were repeatedly electrically stimulated under electrocardiographic monitoring. Colloidal carbon (lml) was injected intravenously immediately after the end of the stimulation and all animals were killed 1 week later. Pathological lesions were identified as carbon deposits visible at gross examination.

RESULTS

Ventricular bigeminy was induced after vagal stimulation in 15 (75%) of the 20 rabbits. Pathological lesions were evident on the basal portion in 16 (80%) and on the mitral valve and papillary muscles of 15 (75%) of the 20 rabbits. Ventricular bigeminy was closely associated with the development of the pathological lesions, which were rarely observed on the ventricular apex.

CONCLUSION

Cardiomyopathic lesions involving the basal portion and mitral complex were frequently induced in rabbits by vagal stimulation. These lesions bear a close similarity in distribution and reversibility to inverted Takotsubo cardiomyopathy.

Tachycardia-mediated cardiomyopathy: recognition and management

Tachycardia-mediated cardiomyopathy is a cause of ventricular dysfunction due to, at least partially, persistent tachycardia leading to cellular and extracellular perturbations. Cardiomyopathy may take years to develop, but pharmacologic management to achieve rate control and reverse remodeling, as well as cardioversion or ablative strategies to stop the tachycardia, can result in rapid recovery from symptoms and gradual improvement in left ventricular ejection fraction. However, ultrastructural changes can remain and may lead to a rapid decline in ventricular function if tachycardia recurs. Ultrastructural changes may also explain a propensity toward sudden death even if the ejection fraction normalizes. Although the etiology, pathophysiology, and late clinical manifestations of tachycardia-mediated cardiomyopathy are beginning to be understood, investigation continues, focusing on prevention, early recognition, and acute and long-term management in an attempt to lessen heart failure and prevent risk of sudden death.

Acute progression of congestive heart failure during paroxysmal supraventricular tachycardia in a patient without structural heart disease

This report presents the case of a 48-year-old male with acute congestive heart failure caused by paroxysmal supraventricular tachycardia. The patient showed no structural heart disease with normal echocardiography parameters of the left ventricle. The pulmonary capillary wedge pressure (PCWP) was continuously monitored during the electrophysiological study. The PCWP and the plasma B-type natriuretic peptide increased from the normal range during ongoing tachycardia. The tachycardia was diagnosed as orthodromic atrioventricular reciprocating tachycardia and it was successfully eliminated by radiofrequency catheter ablation.