Reversible Form Of Cardiomyopathy Research Articles

Mechanisms and Risk Factors for Premature Ventricular Contraction Induced Cardiomyopathy.

Frequent premature ventricular contractions (PVCs) can cause a reversible form of cardiomyopathy in patients without structural heart disease. Because of the challenging nature of PVC-induced cardiomyopathy (PVICM), the mechanisms and risk factors for PVICM are still unclear. Based on the evidence from retrospective and observational studies, the risk factors for the development of PVICM, in addition to PVC exposure, include QRS duration, coupling interval and male sex. Based on animal models, abnormal calcium handling and cardiac remodeling may be the crucial mechanism underlying the development of cardiomyopathy. We have summarized the current knowledge on PVICM in this review. Understanding these mechanisms and risk factors is important for the diagnosis and management of this condition, which can lead to heart failure if left untreated.

Hyponatremia and takotsubo syndrome: a review of pathogenetic and clinical implications.

Hyponatremia is a common electrolyte abnormality with important prognostic and therapeutic implications. It might exert detrimental effects on various organ systems including the central nervous system (CNS), bone, and heart along with its potential association with poor quality of life. These adverse effects might be largely mediated through a variety of mechanisms including osmotic stress, dysfunctional transmembrane exchangers, and enhanced oxidative stress.Interestingly, hyponatremia might also have an important association with takotsubo syndrome (TTS) that has been universally considered as a reversible form of cardiomyopathy usually emerging in response to various stressors. In this context, severe hyponatremia was previously reported to serve as a direct trigger of TTS evolution largely through its potential impact on CNS and heart. However, pathogenetic and clinical implications of hyponatremia still need to be thoroughly evaluated in patients with TTS. This paper aims to analyze the clinical features of published cases with TTS primarily triggered by hyponatremia and also aims to discuss the association between hyponatremia and TTS from a broader perspective.

Left and Right PVC-Induced Ventricular Dysfunction

BackgroundFrequent premature ventricular complexes (PVCs) can result in a reversible form of cardiomyopathy that usually affects the left ventricle (LV). ObjectivesThe objective of this study was to assess whether frequent PVCs have an impact on right ventricular (RV) function. MethodsSerial cardiac magnetic resonance (CMR) studies were performed in a series of 47 patients before and after ablation of frequent PVCs. ResultsPatients with RV cardiomyopathy (ejection fraction [EF] <0.45) had more frequent PVCs than did patients without decreased RV function (23% ± 11% vs 15% ± 11%, P = 0.03). Likewise, patients with LV cardiomyopathy (EF <0.50) had more frequent PVCs than did patients without decreased LV function (23% ± 10% vs 14% ± 12%, P = 0.003). LV dysfunction was present in 21 patients (45%). In patients with LV dysfunction, 15 patients (32%) had biventricular dysfunction, and 6 patients (13%) had isolated LV dysfunction. A total of 19 patients (40%) had RV dysfunction, and 4 of the patients with RV dysfunction (9%) had isolated RV dysfunction. Cardiac magnetic resonance was repeated 1.9 ± 1.3 years after ablation. In patients with successful ablation, RV function improved, and in patients without successful ablation, RV function did not significantly change (before and after ablation RVEF 0.45 ± 0.09 and 0.52 ± 0.09; P < 0.001 vs. 0.46 ± 0.07 and 0.48 ± 0.04; P = 0.14, respectively). ConclusionsFrequent PVCs can cause RV cardiomyopathy that parallels LV cardiomyopathy and is reversible with successful ablation.

Premature Ventricular Complex-Induced Cardiomyopathy.

Frequent premature ventricular complexes (PVCs) can cause an often reversible form of cardiomyopathy. The mechanism for the development of premature ventricular complex-induced cardiomyopathy (PIC) continues to be investigated, and animal models as well as human clinical trials suggest ventricular dyssynchrony to be an important component. In addition to a high PVC burden, this review will detail other risk factors associated with the development of PIC. PVCs can be a marker for the presence of other underlying disease and a thorough work-up, including cardiac magnetic resonance imaging with delayed contrast enhancement, needs to be considered to rule out the presence of structural heart disease. Management of PIC can involve catheter ablation or pharmacotherapy. Multicenter studies have shown a high success rate paired with a low complication rate with catheter ablation, and hence catheter ablation has emerged as the preferred therapeutic option for most patients with PIC. Advances in ablation strategy and technology have enhanced our ability to address certain challenging PVC locations. Important challenges that remain include understanding the coexistence of PIC with other forms of cardiomyopathy, whether there is an associated risk of sudden cardiac death, and the long-term effects on cardiac substrate of exposure to frequent PVCs.

Takotsubo Cardiomyopathy: Is It Due to Adrenal Crisis or Sjogren’s Flare?

Takotsubo cardiomyopathy is a form of reversible cardiomyopathy. It is usually due to sudden emotional or physical stress. It is associated with excessive sympathetic stimulation and catecholamine release. Patients have a very similar presentation to an acute coronary syndrome with patent coronaries. We present a case of takotsubo cardiomyopathy in a patient who has a history of Sjogren’s disease on a steroid taper.

Predictors and Therapy of Cardiomyopathy Caused by Frequent Ventricular Ectopy.

The aim of this review is to describe predictors and therapeutic principles for PVC-induced cardiomyopathy. PVC-induced cardiomyopathy is a treatable condition resulting in a reversible form of cardiomyopathy. PVC-induced cardiomyopathy has only recently been recognized as an entity that causes a reversible form of cardiomyopathy. The mechanism of development of PVC-induced cardiomyopathy has not yet been elucidated, although dyssynchrony appears to play a major role. Multiple factors have been described that are independently associated with PVC-induced cardiomyopathy. Predictors of PVC-induced cardiomyopathy include PVC prevalence, epicardial origin, male gender, longer symptom duration and asymptomatic status, presence of interpolated PVCs, lack of circadian variability, and a broader PVC-QRS width. In the presence of cardiomyopathy, work-up for structural heart disease and its etiology should be performed, followed by aggressive attempts at PVC reduction. There is evidence that ablation therapy is superior to medical therapy for frequent PVCs, but treatment decisions need to be individualized depending on the patients symptoms, PVC prevalence, PVC origin, patients comorbidities, and patient preference. The potential of sudden cardiac death associated with the presence of structural heart disease needs to be recognized, and appropriate risk stratification is mandatory.

Clinical Characteristics and Outcomes of Takotsubo Cardiomyopathy

&lt;p&gt;&lt;span lang="EN-AU"&gt;&lt;span style="font-family: Times New Roman; font-size: medium;"&gt;Takotsubo cardiomyopathy (TC) is a transient, reversible form of cardiomyopathy which predominantly affects post-menopausal women and is an important differential diagnosis of acute coronary syndrome. It is characterised by normal (or near-normal) coronary arteries, regional wall motion abnormalities that extend beyond a single coronary vascular bed, and often proceeded by a stressful event. The pathophysiologic mechanism is complex and remains to be elucidated. There is increasing awareness among physicians about TC and hence, more cases are being reported. The diagnosis of TC has important clinical implications in the management at presentation and afterward. In this review, we discuss the demographics, clinical features, prognosis and management of this cardiomyopathy.&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

Premature Ventricular Complex-induced Cardiomyopathy

Frequent premature ventricular complexes (PVCs) can cause an often reversible form of cardiomyopathy. The mechanism for the development of premature ventricular complex-induced cardiomyopathy (PIC) continues to be investigated, and animal models as well as human clinical trials suggest ventricular dyssynchrony to be an important component. In addition to a high PVC burden, this review will detail other risk factors associated with the development of PIC. PVCs can be a marker for the presence of other underlying disease and a thorough work-up, including cardiac magnetic resonance imaging with delayed contrast enhancement, needs to be considered to rule out the presence of structural heart disease. Management of PIC can involve catheter ablation or pharmacotherapy. Multicenter studies have shown a high success rate paired with a low complication rate with catheter ablation, and hence catheter ablation has emerged as the preferred therapeutic option for most patients with PIC. Advances in ablation strategy and technology have enhanced our ability to address certain challenging PVC locations. Important challenges that remain include understanding the coexistence of PIC with other forms of cardiomyopathy, whether there is an associated risk of sudden cardiac death, and the long-term effects on cardiac substrate of exposure to frequent PVCs.

Effect of circadian variability in frequency of premature ventricular complexes on left ventricular function

Frequent idiopathic premature ventricular complexes (PVCs) can result in a reversible form of cardiomyopathy. The purpose of this study was to assess the impact of variability in PVC frequency throughout the day on PVC-induced cardiomyopathy. The subjects of this study were 107 consecutive patients (58 men [54%]; mean age 49.7 ± 15.0 years; left ventricular ejection fraction 50.4% ± 11.4%) referred for ablation of frequent PVCs. All patients underwent 24-hour Holter monitoring before the ablation procedure. The circadian variation in PVC burden was determined and correlated with the presence or absence of cardiomyopathy. A total of 43 patients (40%) had cardiomyopathy. Patients with cardiomyopathy had an ejection fraction of 38.4% ± 6.9%, a higher PVC burden (28.5% ± 11.5% vs 19.5% ± 10.5%; P = .0001), less variability in circadian PVC distribution (coefficient of variation hourly: 31.5% ± 21% vs 59.8% ± 32.4%; P = .0001), and more frequent interpolated PVCs (20 patients [47%] vs 15 patients [23%]; P = 0.022), and were more frequently asymptomatic than patients without cardiomyopathy (56% vs 19%; P = .0001). In multivariate analysis, consistency in PVC burden throughout the day was an independent predictor of PVC-induced cardiomyopathy (odds ratio 16.3; 95% confidence interval 1.7-155.3; p = 0.015). In patients with frequent PVCs, consistency in hourly PVC frequency throughout the day is an independent predictor of PVC-induced cardiomyopathy.

The consequences of contracting early and often

Frequent premature ventricular contractions (PVCs) are associated with structural heart disease and an increase in sudden and overall mortality. PVCs themselves, if in sufficient numbers, may be associated with the development of a reversible form of cardiomyopathy (CM). A number of small series have suggested that PVC density and features, such as QRS duration, location of origin, and coupling, may increase the predilection to cause CM in structurally normal and diseased hearts. Moreover, elimination of PVCs by catheter ablation has improved ventricular function. Thus, frequent PVCs are a previously underappreciated target for therapeutic intervention in CM. However, the fundamental triggers for the development of myopathy and the details of structural and electrical remodeling have been impeded by the development of a suitable model system. Pacing has been exploited to generate reversible forms of tachycardia-induced CM. Huizar et al have used a premature pacing algorithm to create a model of PVC-induced CM in structurally normal hearts. The algorithm generates a high PVC burden, in this case in a bigeminal pattern pacing from the right ventricular apex. PVC pacing increased the heart rate, on average, from 80 bpm to approximately 130 bpm over 4 months of pacing. Previous characterization of this model demonstrated reversible cardiac dilation and reduced ejection fraction with a compromise in repolarizing reserve evidenced by an increase in ventricular refractory periods. This occurred in the absence of inflammation, fibrosis, increased programmed cell death, or compromised oxidative phosphorylation. In a study reported in this issue of HeartRhythm, Wang et al describe heterogeneously prolonged action potential durations (APD) in myocytes isolated from the left ventricular free wall, associated with reductions in the transient outward (Ito) and inward rectifier (IK1) potassium currents without significant changes in the delayed rectifier (IKr, IKs) currents. The decrease in repolarizing reserve is associated

A Case of Transient Mid-Ventricular Ballooning Syndrome after Cardiac Arrest

일과성 중간 좌심실 풍선 확장 증후군은 스트레스성 심근증의 한 변형으로 중간부 좌심실에 국한된 심근벽 운동장애와 확장을 보이는 질환이다. 임상양상이 급성 관상동맥 증후군과 유사하여 감별 진단이 필요하다는 점에서 중요하며, 정확한 병태생리의 확립을 위한 추가 연구가 요구된다. 본 저자들은 자가 지방 이식 수술 도중 발생한 심정지로 심폐 소생술 시행 후 내원하여 심전도와 심초음파에서 급성 심근경색이 의심되었으나 관상동맥 조영술 및 좌심실 조영술 시행 후 일과성 중간 좌심실 풍선 확장 증후군이 진단된 증례를 경험하여 이를 보고한다.

Stress-related cardiomyopathies

Stress-related cardiomyopathies can be observed in the four following situations: Takotsubo cardiomyopathy or apical ballooning syndrome; acute left ventricular dysfunction associated with subarachnoid hemorrhage; acute left ventricular dysfunction associated with pheochromocytoma and exogenous catecholamine administration; acute left ventricular dysfunction in the critically ill. Cardiac toxicity was mediated more by catecholamines released directly into the heart via neural connection than by those reaching the heart via the bloodstream. The mechanisms underlying the association between this generalized autonomic storm secondary to a life-threatening stress and myocardial toxicity are widely discussed. Takotsubo cardiomyopathy has been reported all over the world and has been acknowledged by the American Heart Association as a form of reversible cardiomyopathy. Four "Mayo Clinic" diagnostic criteria are required for the diagnosis of Takotsubo cardiomyopathy: 1) transient left ventricular wall motion abnormalities involving the apical and/or midventricular myocardial segments with wall motion abnormalities extending beyond a single epicardial coronary artery distribution; 2) absence of obstructive epicardial coronary artery disease that could be responsible for the observed wall motion abnormality; 3) ECG abnormalities, such as transient ST-segment elevation and/or diffuse T wave inversion associated with a slight troponin elevation; and 4) the lack of proven pheochromocytoma and myocarditis. ECG changes and LV dysfunction occur frequently following subarachnoid hemorrhage and ischemic stroke. This entity, referred as neurocardiogenic stunning, was called neurogenic stress-related cardiomyopathy. Stress-related cardiomyopathy has been reported in patients with pheochromocytoma and in patients receiving intravenous exogenous catecholamine administration. The role of a huge increase in endogenous and/or exogenous catecholamine level in critically ill patients (severe sepsis, post cardiac resuscitation, post tachycardia) to explain the onset of myocardial dysfunction was discussed. Further research is needed to understand this complex interaction between heart and brain and to identify risk factors and therapeutic and preventive strategies.

Relation of symptoms and symptom duration to premature ventricular complex–induced cardiomyopathy

Frequent idiopathic premature ventricular complexes (PVCs) can result in a reversible form of cardiomyopathy. In this study, the determinants of PVC-induced left ventricular (LV) dysfunction were assessed. The subjects of this study were 241 consecutive patients (115 men [48%], mean age 48 ± 14 years) referred for ablation of frequent PVCs. One hundred eighty patients (75%) experienced palpitations and 61 (25%) did not. The PVC burden was determined by 24-hour Holter monitoring, and echocardiograms were performed to assess LV function. An LV ejection fraction of <50% was considered abnormal. LV ejection fraction (mean 0.36 ± 0.09) was present in 76 of 241 patients (32%). There was a higher prevalence of males among the patients with PVC cardiomyopathy compared to patients with normal LV function (51/76 [67%] vs 64/165 [39%]; P <.0001). The mean PVC burden was significantly higher in patients with PVC cardiomyopathy than in patients with normal LV function (28% ± 12% vs 15% ± 13%; P <.0001). Among symptomatic patients, those with cardiomyopathy had a significantly longer duration of palpitations (135 ± 118 months) compared with patients with normal LV function (35 ± 52 months; P <.0001). The proportion of asymptomatic patients was significantly higher in the presence of cardiomyopathy (36/76, 47%) than in normal LV function (25/165, 15%; P <.0001). Symptom duration of 30 to 60 months, symptom duration >60 months, the absence of symptoms, and the PVC burden in asymptomatic patients were independent predictors of impaired LV function (adjusted odds ratio [95% confidence interval]: 4.0 [1.1-14.4], 20.1 [6.3-64.1], 13.1 [4.1-37.8], and 2.1 [1.2-3.6], respectively). The duration of palpitations and the absence of symptoms are independently associated with PVC-induced cardiomyopathy.

Atypical "mid-ventricular" Tako-tsubo cardiomyopathy in a patient suffering from posttraumatic stress disorder: A case report

The syndrome of "left ventricular ballooning" summarizes an acute onset of transient extensive akinesia of several segments (apical, mid-ventricular) of the left ventricle, without significant lesions on the coronary angiogram, accompanied by chest symptoms, electrocardiographic changes, and limited release of cardiac markers disproportionate to the extent of akinesia. Initially, the vast majority of cases has been reported among Japanese population. Emotional or physical stress or other preceding triggering factors might play a key role in this reversible form of cardiomyopathy, but the precise etiology remains unknown. We describe a case of a 52-year-old woman with posttraumatic stress disorder after cerebral bleeding presenting with an atypical form of left ventricular ballooning ("midventricular ballooning") syndrome.

Stress-Induced Cardiomyopathy

Stress-induced cardiomyopathy (SIC) is an increasingly recognized disease entity and is accepted as a unique form of reversible cardiomyopathy. Typical apical ballooning precipitated by emotional stress with clinical features mimicking acute coronary syndrome and rapid recovery was a hallmark of SIC. Along with cumulative experiences, new features are well appreciated. These include atypical ballooning patterns (mid-ventricular and basal ballooning), contribution of physical stressors (acute medical illnesses and routine diagnostic and therapeutic procedures including surgery) to the development of SIC, and development of serious complications such as right ventricular dysfunction, thrombus formation, and left ventricular outflow tract obstruction with significant mortality rate and occasional recurrence, representing diverse clinical spectrum of SIC. Although the exact mechanism and standard treatment of SIC has not been established, physicians’ vigilance is needed for prompt diagnosis and adequate treatment for this potentially fatal disorder. Echocardiography can play a role as an easy and noninvasive imaging modality.

Stress cardiomyopathy syndrome: A contemporary review

Stress cardiomyopathy (SC) syndrome represents a reversible form of cardiomyopathy that commonly presents proximate to an acute emotional or physiologic stressor. The clinical presentation is similar to an acute coronary syndrome in the absence of obstructive coronary artery disease to explain the unusual distribution of associated transient wall motion abnormalities. Postmenopausal women seem particularly prone to SC for unclear reasons. The pathophysiology of the syndrome is unknown but may involve pathologic sympathetic myocardial stimulation.

Impact of radiofrequency ablation of frequent post-infarction premature ventricular complexes on left ventricular ejection fraction

Frequent idiopathic premature ventricular complexes (PVC) are associated with a reversible form of cardiomyopathy. The effect of frequent PVCs on left ventricular function has not been evaluated in post-infarction patients. This study sought to evaluate the value of post-infarction PVC ablation and possible determinants of a reversible cardiomyopathy. Thirty consecutive patients (24 men, age 61 +/- 12, left ventricular ejection fraction [LVEF] 0.36 +/- 0.12) with remote myocardial infarction referred for implantable cardioverter-defibrillator (ICD) implantation for primary prevention of sudden death or for management of symptomatic ventricular tachycardia or PVCs were evaluated. Fifteen patients with a high PVC burden (>or=5% of all QRS complexes on 24-h Holter monitor) underwent mapping and ablation of PVCs before ICD implantation. The remaining 15 patients served as a control group. LVEF was assessed by echocardiography, and scar burden was assessed by cardiac magnetic resonance imaging with delayed enhancement (DE-MRI) in both groups. PVC ablation was successful in 15 of 15 patients and reduced the mean PVC burden from 22 +/- 12% to 2.6 +/- 5.0% (P <.001). After the procedure, LVEF increased significantly from 0.38 +/- 0.11 to 0.51 +/- 0.09 in the PVC ablation group (P = .0001). In the control group, LVEF remained unchanged within the same time frame (0.34 +/- 0.14 vs. 0.33 +/- 0.15; P = .6). Patients with frequent PVCs had a significantly smaller scar burden by DE-MRI compared with control patients. Five of the patients with frequent PVCs underwent ICD implantation. Post-infarction patients with frequent PVCs may have a reversible form of cardiomyopathy. DE-MRI may identify patients in whom the LVEF may improve after ablation of frequent PVCs.

The“Broken Heart Syndrome”: Understanding Takotsubo Cardiomyopathy

"Broken heart syndrome," or takotsubo cardiomyopathy, is a spontaneously reversible form of cardio-myopathy that is often induced by emotional or physical stress. Signs and symptoms include chest pain, dyspnea, electrocardiographic changes, and elevated levels of cardiac biomarkers. Patients often have signs and symptoms of fluid overload and can have acute pulmonary edema. Most patients are postmenopausal women, many with no risk factors for coronary artery disease. The left ventricular abnormality reverses spontaneously in days or weeks.

Persistent left ventricular dilatation in tachycardia-induced cardiomyopathy patients after appropriate treatment and normalization of ejection fraction

Tachycardia-induced cardiomyopathy (TIC) seems to be a form of reversible cardiomyopathy. With recurrence, TIC can be more severe and may increase the risk for sudden cardiac death. We postulate that negative remodeling persists even though ejection fraction (EF) normalizes after appropriate treatment in these patients. We analyzed 2-dimensional echocardiographic parameters of 24 patients with TIC (male: 21; age: 64.1 +/- 15.2 years; atrial arrhythmias: 92%) that improved significantly with treatment (mean time between pretreatment and posttreatment echocardiography: 14 +/- 6 months) and compared them with that of age-, gender-, and ejection fraction-matched control subjects without a history of TIC. The majority of posttreatment echocardiographic parameters showed a significant improvement (P <.05) with treatment in patients with TIC, including left ventricular (LV) ejection fraction (31.2% +/- 8.2% to 55.0% +/- 5.7%) and LV end systolic volume index (55 +/- 21 ml/m(2) to 33 +/- 13 ml/m(2)). There was no significant difference in LV end diastolic volume index (78 +/- 22 ml/m(2) to 72 +/- 22 ml/m(2), P = .15). However, when compared with age-, gender-, and ejection fraction-matched control subjects, posttreatment echocardiographic parameters in TIC patients showed significant differences (TIC vs control group) in LV end systolic volume index (33 +/- 13 ml/m(2) vs 22 +/- 5 ml/m(2)), LV end diastolic volume index (72 +/- 22 ml/m(2) vs 51 +/- 12 ml/m(2)), and cardiac index (2.6 +/- 0.8 l/min/m(2) vs 1.8 +/- 0.6 l/min/m(2)). Although the majority of echocardiographic parameters, including EF, improved significantly with treatment in TIC patients, LV dimensions and volumes remained significantly elevated when compared with control subjects, indicating persistence of negative LV remodeling, even after appropriate treatment and normalization of EF at a mean follow-up of 14 months.

Tako-tsubo cardiomyopathy

Tako-tsubo cardiomyopathy (transient left ventricular apical ballooning) is a reversible form of cardiomyopathy of unknown etiology. Tako-tsubo Cardiomyopathy (TTC) is typically precipitated by sudden emotional or physical stress, and is associated with excessive sympathetic stimulation and catecholamine release. Its clinical presentation is similar to that of acute coronary syndrome. The diagnosis of TTC must be considered in all patients who develop a transient left ventricular apical (or mid ventricular) ballooning in the absence of obstructive coronary artery disease. Although the prevalence of TTC remains unknown, approximately 2% of all patients presenting with a presumed diagnosis of acute myocardial infarction have been found to have this syndrome. An illustrative case report and literature review is provided.