Incessant fascicular tachycardia: a cause of arrhythmia induced cardiomyopathy

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.

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.

Recovery and recurrence of left ventricular systolic dysfunction in patients with idiopathic dilated cardiomyopathy

BACKGROUND

Some patients with nonischemic left ventricular (LV) systolic failure recover to have normal LV systolic function. However, few studies on the rates of recovery and recurrence have been reported, and no definitive indicators that can predict the recurrence of LV dysfunction in recovered idiopathic dilated cardiomyopathy (IDCMP) patients have been determined. It was hypothesized that patients who recovered from nonischemic LV dysfunction have a substantial risk for recurrent heart failure.

METHODS

Forty-two patients (32 men) with IDCMP (mean [+/- SD] age 56.9+/-8.7 years) who recovered from systolic heart failure (LV ejection fraction [LVEF] of 26.5+/-6.9% at initial presentation) to a near-normal state (LVEF of 40% or greater, and a 10% increase or greater in absolute value) were monitored for recurrence of LV systolic dysfunction. Patients with significant coronary artery disease were excluded. Patients were monitored for 41.0+/-26.3 months after recovery (LVEF 53.4+/-7.6%) from LV dysfunction.

RESULTS

LV systolic dysfunction reappeared (LVEF 27.5+/-8.1%) during the follow-up period in eight of 42 patients (19.0%). No significant difference between the groups with or without recurrent heart failure was observed in the baseline clinical and echocardiographic characteristics. However, more patients in the recurred IDCMP group than those in the group that maintained the recovery state had discontinued antiheart failure medication (62.5% versus 5.9%, P<0.05).

CONCLUSIONS

LV dysfunction recurs in some patients with reversible IDCMP. The recurrence was significantly correlated with the discontinuation of antiheart failure drugs. The results suggest that continuous medical therapy may be mandatory in patients who recover from LV systolic dysfunction.

Diagnostic approach and treatment strategy in tachycardia-induced cardiomyopathy

BACKGROUND

Due to the absence of differential guidelines for heart failure with tachyarrhythmia, it is difficult to diagnose tachycardia-induced cardiomyopathy (TIC) at the initial visit. Furthermore, clinical outcomes of rate versus rhythm control in TIC are unclear.

HYPOTHESIS

Because the etiology of TIC is different from dynamic cardiomyoplasty (DCMP), differential parameters may be present.

METHODS

We assessed 21 patients with TIC (15 men; mean age, 50+/-14 years) and 21 control patients with idiopathic DCMP. We assessed clinical courses, echocardiographic parameters, as well as outcomes by treatment.

RESULTS

In the TIC group, the related tachyarrhythmias were atrial fibrillation (n=12), atrial flutter (n=5), atrial tachycardia (n=3) and paroxysmal supraventricular tachycardia (n=1). After treatment, all patients became asymptomatic and the ejection fraction (EF) improvement (DeltaEF>or=15%) was observed in all patients (left ventricular ejection fraction [LVEF], 30+/-11%initial versus 58+/-6%last). In the idiopathic DCMP group, no patient showed EF improvement (EF increase

CONCLUSIONS

In patients presented as heart failure with tachyarrhythmia, initial echocardiographic parameters, especially LV end-diastolic dimension, help to differentiate TIC from idiopathic DCMP. Rate control was as effective as rhythm control for EF improvement and prognosis.

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Key Words

• dynamic cardiomyoplasty
• tachycardia‐induced cardiomyopathy
• echocardiography
• left ventricle end‐diastolic dimension
• clinical outcomes
• rate control
• rhythm control

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MESH Headings

• Adult
• Aged
• Cardiomyopathies/diagnosis
• Cardiomyopathies/etiology
• Cardiomyopathies/physiopathology
• Cardiomyopathies/therapy
• Diagnosis, Differential
• Echocardiography
• Female
• Humans
• Male
• Middle Aged
• Stroke Volume
• Tachycardia/complications
• Tachycardia/therapy
• Ventricular Function, Left

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Affiliation(s)

Young‐Hoon Jeong Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
Kee‐Joon Choi Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
Jong‐Min Song Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
Eui‐Seock Hwang Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
Kyoung‐Min Park Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
Gi‐Byoung Nam Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
Jae‐Joong Kim Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
You‐Ho Kim Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea

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Reversal of dilated cardiomyopathy by the elimination of frequent left or right premature ventricular contractions

BACKGROUND

RF ablation of frequent premature ventricular contractions (PVC) has recently been shown to improve left ventricular (LV) systolic function and dimensions in a few patients, however mainly when they originated from the right ventricular outflow tract.

METHODS

RF ablation was performed at various ventricular locations in six consecutive patients with frequent, isolated PVC associated with idiopathic dilated cardiomyopathy (DCM). Baseline clinical status, PVC counts, LV ejection fraction (EF) and end-diastolic diameter (EDD) were recorded at baseline and at 6 months of follow-up.

RESULTS

PVC ablation was performed in the right ventricle in four patients, the left ventricle in two patients. Before RF ablation, five patients were in New York Heart Association (NYHA) functional class I, and one patient was in class II. After RF ablation, the mean PVC count/24 h decreased from 17,717 +/- 7,100 to 268 +/- 366 (p = 0.006) while LVEF increased from 42 +/- 2.5% to 57 +/- 3% (p = 0.0001) and LVEDD decreased from 60.0 +/- 3.5 to 54.0 +/- 3.7 mm (p = 0.0009). The clinical status normalized with regression of palpitations and NYHA class.

CONCLUSIONS

Elimination of frequent isolated PVC in patients with DCM with RF can normalize the clinical status and LV systolic function and dimensions, regardless of the morphology or origin of the PVC.

Characteristics of Congestive Heart Failure Accompanied by Atrial Fibrillation With Special Reference to Tachycardia-Induced Cardiomyopathy

BACKGROUND

Sustained tachycardia causes left ventricular (LV) systolic dysfunction leading to heart failure (HF), which is widely known as "tachycardia-induced cardiomyopathy (TIC)", but its prevalence and prognosis in Japanese remain unclear.

METHODS AND RESULTS

Of 213 consecutive patients with HF associated with atrial fibrillation (AF) requiring hospitalization (n=213) between January 1999 and December 2004, and 104 (83 males, 67+/-12.6 years) were identified as not having any structural heart disease. Of them 41 (39%) had a normal LV ejection fraction (LVEF) at the initial admission, and the remaining patients fell into 2 groups: those with rapid (<6 months) normalization of the LVEF after AF management (presumed TIC, 30 patients, 29%) and those with persistent LV systolic dysfunction (dilated cardiomyopathy (DCM), 33 patients, 32%). Although the B-type natriuretic peptide value and LVEF did not differ between the 2 groups, the LV size on admission was significantly smaller in the TIC group (LV end-diastolic dimension (LVDd) 57.6+/-7.2, LV end-systolic dimension (LVDs) 49.4+/-8.0) than in the DCM group (LVDd 63.4 +/-8.8, LVDs 55.3+/-9.6, p<0.05). During a follow-up period of 42.1+/-21.2 months, cardiac death and recurrent HF hospitalization were significantly less frequent in the TIC group than in the DCM group.

CONCLUSIONS

In AF-associated HF requiring hospitalization, TIC is the presumed cause in approximately one-third of patients without any previously known structural heart disease. That particular group is characterized by a relatively smaller LV and better prognosis under medical treatment.

Reversal of Cardiomyopathy in Patients With Repetitive Monomorphic Ventricular Ectopy Originating From the Right Ventricular Outflow Tract

Background— Tachycardia-induced cardiomyopathy caused by ventricular tachycardia is a well-defined clinical entity. Less well appreciated is whether simple ventricular ectopy can result in cardiomyopathy. We sought to examine a potential causal relationship between repetitive monomorphic ventricular ectopy originating from the right ventricular outflow tract and cardiomyopathy and the role of ablation in reversing this process.

Methods and Results— The study consisted of 27 patients (11 men; age, 47±15 years) with repetitive monomorphic ventricular ectopy, including 8 patients (30%) with depressed ventricular function (ejection fraction ≤45%). All patients underwent assessment of cardiac structure and function. The burden of ectopy was quantified through 24-hour Holter monitoring. Patients then underwent ablation guided by 3D mapping. After ablation, patients underwent repeated Holter monitoring and reassessment of cardiac function. Patients with depressed ventricular function were more likely to be older than patients with normal function (58±14 versus 42±18 years; P =0.013). However, the burden of ventricular ectopy was similar in patients with (17 859±13 488 ectopic beats per 24 hours) and without (17 541±11 479 ectopic beats per 24 hours; P =0.800) preserved ventricular function. Successful ablation was performed in 23 patients (85%), including 7 of 8 patients with depressed ventricular function. In this latter group, ventricular function improved in all patients (from 39±6% to 62±6%; P =0.017).

Conclusions— Repetitive monomorphic ventricular ectopy (in the absence of sustained ventricular tachycardia) originating from the right ventricular outflow tract is an underappreciated cause of unexplained cardiomyopathy. Successful ablation of the focal source of ventricular ectopy results in normalization of left ventricular function. Patients with ectopy-induced cardiomyopathy are significantly older than patients with preserved ventricular function, which suggests either that older patients are more susceptible to the development of a cardiomyopathy or that the cardiomyopathy has had a longer period of time in which to evolve.

Heart Failure and Sudden Death in Patients With Tachycardia-Induced Cardiomyopathy and Recurrent Tachycardia

BACKGROUND

Tachycardia-induced cardiomyopathy is a reversible cause of heart failure. We hypothesized that although left ventricular ejection fraction measurements normalize after heart rate or rhythm control in patients with tachycardia-induced cardiomyopathy, recurrent tachycardia may have abrupt and deleterious consequences.

METHODS AND RESULTS

Patients with tachycardia-induced cardiomyopathy that developed over years were evaluated and treated. Tachycardia episodes and outcomes were assessed. Twenty-four patients were identified. All had NYHA functional class III heart failure or greater on presentation. One third were heart transplant candidates. There were 17 men and 7 women with a mean age of 46+/-16 years and mean left ventricular ejection fraction of 0.26+/-0.09 at the index visit. The cause was atrial fibrillation (n=13), atrial flutter (n=4), atrial tachycardia (n=3), idiopathic ventricular tachycardia (n=1), permanent junctional reciprocating tachycardia (n=2), and bigeminal ventricular premature contractions (n=1). Within 6 months of rate control or correction of the rhythm, left ventricular ejection fraction improved or normalized and symptoms abated in all. Five patients had tachycardia recur. In these patients, left ventricular ejection fraction dropped precipitously and heart failure ensued within 6 months, even though the initial impairment took years. Rate control eliminated heart failure and improved or normalized ejection fraction in 6 months. Three of 24 patients died suddenly and unexpectedly.

CONCLUSIONS

Tachycardia-induced cardiomyopathy develops slowly and appears reversible by left ventricular ejection fraction improvement, but recurrent tachycardia causes rapid decline in left ventricular function and development of heart failure. Sudden death is possible.

Tachycardia-induced cardiomyopathy

Systolic dysfunction associated with chronic tachyarrhythmias, known as tachycardia-induced cardiomyopathy, is a reversible form of heart failure characterized by left ventricular dilatation that is usually reversible once the tachyarrhythmia is controlled. Its development is related to both atrial and ventricular arrhythmias. The diagnosis is usually made following observation of a marked improvement in systolic function after normalization of heart rate. Clinicians should be aware that patients with unexplained systolic dysfunction may have tachycardia-induced cardiomyopathy, and that controlling the arrhythmia may result in improvement and even complete normalization of systolic function.

Radiofrequency catheter ablation of upper septal idiopathic left ventricular tachycardia exhibiting left bundle branch block morphology

Idiopathic left ventricular (LV) tachycardia usually exhibits right bundle branch block morphology. There are only a few sporadic cases that exhibit left bundle branch block (LBBB) morphology. We report a patient whose QRS complex during ventricular tachycardia (VT) was relatively narrow (100 msec) and exhibited LBBB (precordial R wave transition between V3 and V4) and a normal frontal plane axis. This VT was ablated successfully by radiofrequency current applied to the LV upper septum, where the earliest endocardial activation was recorded.