1/56. Reversible catecholamine-induced cardiomyopathy in a heart transplant candidate without persistent or paroxysmal hypertension.BACKGROUND: Both dilated and hypertrophic cardiomyopathy have been reported in patients with pheochromocytoma, who were almost always hypertensive. The outcome frequently has been fatal, yet cardiac dysfunction can be reversible after medical or surgical therapy for the pheochromocytoma. methods: We report the case of a patient with dilated cardiomyopathy without persistent or paroxysmal hypertension, who was found to have a pheochromocytoma during initial medical evaluation. RESULTS: The identification and treatment of the pheochromocytoma led to significant improvement in cardiac function and cardiac transplantation was avoided. CONCLUSIONS: This case illustrates some unusual features in pheochromocytoma-induced cardiomyopathy: (1) absence of persistent or paroxysmal hypertension, (2) initial presentation with acute myocardial infarction and normal coronary arteries, and (3) recurrent episodes of nonsustained ventricular tachycardia.- - - - - - - - - - ranking = 1keywords = dysfunction (Clic here for more details about this article) |
2/56. A case of thyrotoxicosis and reversible systolic cardiac dysfunction.A woman with congestive heart failure and reduced left ventricular ejection fraction associated with hyperthyroidism is reported. Congestive heart failure resolved and left ventricular ejection fraction normalized within three weeks of treatment of her hyperthyroidism. The literature on previously reported cases of reversible systolic heart failure associated with hyperthyroidism is reviewed and the possible mechanisms leading to systolic dysfunction and congestive heart failure in thyrotoxicosis are discussed. One such mechanism may be the action of thyroid hormone on altering gene expression in cardiac cells; another could be the chronic tachycardia associated with thyrotoxicosis. Although it is a not a common cause of systolic heart failure, thyrotoxicosis should be considered in the differential diagnosis of cardiomyopathies because it is a potentially reversible cause.- - - - - - - - - - ranking = 5keywords = dysfunction (Clic here for more details about this article) |
3/56. Isolated noncompaction of the myocardium: an exceedingly rare cardiomyopathy. A case report.Isolated noncompaction of the left ventricular myocardium is a rare cardiac disorder due to an arrest in myocardial morphogenesis. It is characterized by prominent and excessive trabeculation in a ventricular wall segment, with deep intertrabecular spaces perfused from the ventricular cavity. Echocardiographic findings are important clues for the diagnosis. Clinical symptoms include signs of left ventricular systolic dysfunction even to the point of heart failure, ventricular arrhythmias, and embolic events. We describe an adult case in whom the only clinical symptoms were life-threatening ventricular arrhythmias. Transthoracic echocardiography did not contribute to the diagnosis, which was made thanks to left ventricular contrast angiography. Electrophysiological testing induced a fast monomorphic sustained ventricular tachycardia, with hemodynamic impairment, that was refractory to pharmacological treatment, and for this reason a permanent cardioverter-defibrillator was implanted. A subsequently performed transesophageal echocardiographic examination showed a localized, regional increase in left ventricular wall thickness and degree of trabeculation. The causes and electrophysiological mechanisms of arrhythmias in noncompaction are still unknown: grossly irregular branching and connecting of myocardial fascicles in the noncompacted segments, isometric contraction with increased wall stress, and localized coronary perfusion impairment can all induce disorganized or delayed activation and increase the potential for arrhythmias. This is the first reported case of noncompaction in which an implantable defibrillator was used to control life-threatening arrhythmias.- - - - - - - - - - ranking = 1keywords = dysfunction (Clic here for more details about this article) |
4/56. A new off-pump technique for thoratec right ventricular assist device insertion.The need for right ventricular support as an adjunct to left ventricular assistance is uncommon. When required, the insertion of a right ventricular assist device may be complicated by preexisting hepatic dysfunction, coagulation abnormalities, and renal failure, all of which are exacerbated by cardiopulmonary bypass. We report a technique for insertion of a right ventricular assist device without the need for cardiopulmonary bypass.- - - - - - - - - - ranking = 1keywords = dysfunction (Clic here for more details about this article) |
5/56. Combined cardiomyopathy and skeletal myopathy: a variant with atrial fibrillation and ventricular tachycardia.This article describes a family characterized by combined cardiomyopathy and nonspecific skeletal myopathy who present in the third to fifth decades with cardiac manifestations but earlier have evidence of subtle skeletal muscle dysfunction. They differ from previously defined syndromes and potentially represent a different genetic expression or mutation. Cardiomyopathy presents with atrial arrhythmias including AF and atrial flutter. life-threatening ventricular tachyarrhythmias occur next with onset of ventricular dysfunction. Electrophysiological study revealed sustained monomorphic VT. Affected family members benefitted from an ICD and progression to congestive heart failure (CHF) occurred late. Skeletal myopathy continues with marked progressive muscle weakness and inability to ambulate without assistance. Genetic analysis is currently ongoing. Neurological evaluation in all three family members revealed nonspecific myopathy affecting the psoas and iliopsoas muscles. atrophy and wasting of the facial and temporalis muscles were common. Skeletal muscle biopsy revealed myofiber atrophy consistent with myopathy.- - - - - - - - - - ranking = 358.26822888402keywords = ventricular dysfunction, dysfunction (Clic here for more details about this article) |
6/56. verapamil-sensitive left ventricular tachycardia in patients with coronary artery disease: clinical and electrophysiologic features consistent with triggered activity.This is a retrospective review of three male patients with verapamil-sensitive left ventricular tachycardia, severe coronary artery disease, and past myocardial infarction. Each patient had severe left ventricular dysfunction (mean ejection fraction 34%). Each tachycardia had a right bundle branch block/left axis deviation morphology, which was sustained with isoproterenol. One patient had incessant tachycardia 3 days after coronary bypass surgery. electrophysiology and clinical parameters were suggestive of triggered activity rather than reentry. Each tachycardia was terminated with verapamil but failed with adenosine, beta blockers, and class I/III antiarrhythmics. Prior cases of verapamil-sensitive ventricular tachycardia have been seen in patients without organic heart disease, and the putative mechanism appears to be reentry. These patients with ischemic coronary artery disease may exhibit a mechanism of triggered activity in the Purkinje system region, which is responsive to calcium channel blockade. Successful radiofrequency ablation was guided by Purkinje potentials.- - - - - - - - - - ranking = 481.82181011772keywords = ventricular dysfunction, left ventricular dysfunction, dysfunction (Clic here for more details about this article) |
7/56. Case report: regional cerebral hypoperfusion induced by ventricular tachycardia - short-term hippocampal hypoperfusion and its potential relationship to selective neuronal damage.BACKGROUND: Focussing on regional cerebral hypoperfusion during hemodynamically stable, but borderline hypotensive, sustained ventricular tachycardia (VT) experimental studies show (1) a reduction of cerebral blood flow (CBF) during tachyarrhythmias in contrast to the concept of CBF autoregulation, (2) a mediation of hypoperfusion by neuronal and humoral mechanisms, and (3) an involvment of microcirculation due to an ischemic stress response of the cerebral tissue. The clinical relevance of these observations remains still unclear. CASE REPORTS: Two patients with coronary artery disease, left ventricular dysfunction and sustained monomorphic VT underwent electrophysiological study. VT was induced and the tracer (99m)Tc-HMPAO was injected after 3 minutes of ongoing VT. Regional CBF during this life threatening arrhythmia was determined with brain SPECT. A scanning protocol was performed after termination of VT. The measurements were repeated at baseline during normofrequent sinus rhythm (SR) one week later. CBF during SR was significantly reduced in the temporal lobe in comparison to the conditions during stable VT, particularly in the left hippocampus. CONCLUSION: The reduction of hippocampal CBF due to cerebrovascular vasoconstriction and neuronal reflex mechanism previously observed in experiments during stable, sustained VT can be confirmed in a clinical scenario by high resolution (99m)Tc-HMPAO brain SPECT. This supports the hypothesis that repetitive stable VT can play a role in the pathophysiology of cerebrovascular insufficiency. Further clinical studies are needed to analyze the impact of tachyarrhythmias on cognitive and mnemic function.- - - - - - - - - - ranking = 481.82181011772keywords = ventricular dysfunction, left ventricular dysfunction, dysfunction (Clic here for more details about this article) |
8/56. Benefit of pacing and beta-blockers in idiopathic repetitive polymorphic ventricular tachycardia.An 18-year-old woman presented with recurrent exercise-induced syncopal episodes and severe systolic dysfunction. ECG monitoring disclosed repetitive polymorphic ventricular complexes, paroxysms of bidirectional ventricular tachycardia, and nonsustained bursts of slow polymorphic ventricular tachycardia that increased in length and rate during exercise. Ventricular arrhythmias were refractory to medical treatment, which included verapamil and beta-blockers. Addition of permanent atrial pacing to beta-blocker therapy suppressed the arrhythmias and reversed systolic impairment in the following months.- - - - - - - - - - ranking = 1keywords = dysfunction (Clic here for more details about this article) |
9/56. Active lymphocytic myocarditis treated with murine OKT3 monoclonal antibody in a patient presenting with intractable ventricular tachycardia.This report describes the case of a 33-year-old woman with biopsy-proven, active lymphocytic myocarditis manifested by intractable ventricular tachycardia, nonspecific intraventricular block, and myocardial dysfunction. We treated hersuccessfully with OKT3 monoclonal antibody and antiarrhythmic agents. immunosuppression is not recommended in patients with infectious or postinfectious myocarditis. However, it may have an important role in autoimmune myocarditis. In the few reports in the medical literature that we were able to find, OKT3 monoclonal antibody was administered early in the setting of acute, fulminant autoimmune myocarditis. Our patient received OKT3 therapy in a later phase of the disease, when inflammatory infiltrates were accompanied by extensive fibrosis and severe damage of cardiomyocytes. Our patient had concomitant helicobacter pylori infection and a strong positive family history of gastric cancer, a disease often associated with H. pylori. We discuss the possibility of a causal relationship between H. pylori infection and autoimmune myocarditis.- - - - - - - - - - ranking = 1keywords = dysfunction (Clic here for more details about this article) |
10/56. A novel SCN5A mutation associated with long QT-3: altered inactivation kinetics and channel dysfunction.Mutations in the gene (SCN5A) encoding the alpha-subunit of the cardiac Na channel cause congenital long qt syndrome (LQT-3). Here we describe a novel LQT-3 mutation I1768V (I1768V) located in the sixth transmembrane spanning segment of domain IV. This mutation is unusual in that it is located within a transmembrane spanning domain and does not promote the typically observed sustained inward current corresponding to a gain of channel function (bursting). Rather, I1768V increases the rate of recovery from inactivation and increases the channel availability, observed as a positive shift of the steady-state inactivation curve ( 7.6 mV). Using a Markovian model of the cardiac Na channel, we simulated these changes in gating behavior and demonstrated that a small increase in the rate of recovery from inactivation is sufficient to explain all of the experimentally observed current changes. The effect of these alterations in channel gating results in an increase in window current that may act to disrupt cardiac repolarization.- - - - - - - - - - ranking = 4keywords = dysfunction (Clic here for more details about this article) |
| | Next -> |