Catheter ablation of multiple accessory pathways in duchenne muscular dystrophy.

A 23-year-old male with Duchenne muscular dystrophy (DMD) experienced self-limiting palpitations at age 19 years for the first time. Palpitations recurred not earlier than at age 23 years, and were attributed to narrow complex tachycardia, which could be terminated with adenosine. Since electrocardiography showed a delta-wave, Wolff-Parkinson-White (WPW) syndrome was diagnosed, ajmaline prescribed and radio-frequency catheter ablation of three accessory pathways carried out one week later. One day after ablation, however, a relapse of the supraventricular tachycardia occurred and was terminated with ajmaline. Re-entry tachycardia occurred a second time six days after ablation, and as before, it was stopped only with ajmaline. Despite administration of verapamil to prevent tachycardia, it occurred a third time four months after ablation. This case shows that cardiac involvement in DMD may manifest also as WPW-syndrome. In these patients, repeated radio-frequency catheter ablation of accessory pathways may be necessary to completely block the re-entry mechanism.

Novel c.367_369del LMNA mutation manifesting as severe arrhythmias, dilated cardiomyopathy, and myopathy.

OBJECTIVE: The 3-bp deletion in exon 2 of the Lamin A/C (LMNA) gene has not been described in association with dilated cardiomyopathy, which is characterized by progressive heart failure, atrioventricular (AV) block, tachyarrhythmias, and variable skeletal muscle involvement. CASE REPORT: In a 43-year-old woman with a long-term history of palpitations and newly diagnosed AV blocks I and II, ventricular ectopic beats, inducible nonsustained ventricular tachycardias (VTs), cardiac arrest, and successful resuscitation, an implantable cardioverter defibrillator was successfully implanted. Her family history was positive for sudden cardiac death (her father and sister), dyspnea and heart failure (her grandmother and sister), palpitations (her brother), and elevated levels of creatine-kinase (CK) (her sister). Two cousins had died of nonspecific muscular dystrophy at ages 10 years and 11 years. Upon neurological investigations revealing sore neck muscles, reduced tendon reflexes, and detached, spot-like white matter lesions bilaterally, a neuromuscular disorder was suspected. The direct sequencing of all exons and flanking intronic regions of the LMNA gene detected the heterozygote 3-bp deletion (AAG) c.367_369del in exon 2 of the gene. This mutation resulted in the deletion of a lysine at position 123 (p.lys123del) in the lamin A/C protein. CONCLUSIONS: The novel 3-bp deletion in exon 2 of the LMNA gene may phenotypically manifest as dilated cardiomyopathy, heart failure, severe tachyarrhythmias, and muscular dystrophy. Sudden cardiac death from ventricular fibrillation may be prevented in LMNA mutation carriers if the diagnosis is established early enough to implant a cardioverter defibrillator.

Complete heart block associated with noncompaction, nail-patella syndrome, and mitochondrial myopathy.

OBJECTIVES: Complete heart block has not been reported in association with left ventricular hypertrabeculation (LVHT)/noncompaction, nail-patella syndrome (NPS), and mitochondrial myopathy (MMP). CASE REPORT: A 47-year-old man with congenital NPS from a 17-bp deletion in exon 5 of the LMX1B gene, MMP from the A3243G mitochondrial DNA transition, and LVHT was acutely admitted after a syncope followed by dizziness. Cardiological examinations revealed bradycardia. Blood pressure was 70/30 mm Hg. Blood work revealed a creatine kinase of 389 U/L (normal, <175 U/L), renal insufficiency, anemia, and reduced calcium, phosphorus, and magnesium. Electrocardiogram showed complete heart block with an escape rhythm of 30/min. A temporary pacemaker was inserted. During the procedure, the patient became asystole but was successfully resuscitated. One day later, he received a permanent pacemaker. Echocardiography showed normal systolic function and LVHT. The patient recovered without sequelae. CONCLUSION: In single cases, LVHT may be associated with complete heart block. Most likely, complete heart block was due to MMP. Patients with NPS and MMP require multidisciplinary surveillance, including regular electrocardiograms, for indicating anticipatory intervention in time.

Long lasting impaired cerebral blood flow after ecstasy intoxication.

Four hours after having taken 10 ecstasy tablets a Grand Mal seizure occurred in a 19-year-old woman followed by coma, hyperthermia, tachycardia, tachypnea, and renal failure. After awakening she was oriented but presented with helplessness, disconcertion, hallucinations, panic attacks, and amnesic syndrome. Computed tomography and magnetic resonance imaging scans of the brain were normal. [99Tc]-hexamethylpropyleneamine oxime (HMPAO)-single photon emission computed tomography (SPECT), 20 days after intoxication, showed reduced, inhomogeneous, supratentorial tracer uptake bilaterally. Electroencephalography (EEG) disclosed diffuse slowing and occasionally generalized sharp waves. Valproic acid was begun. Except for slight amnesia, neuropsychological deficits had disappeared and [99Tc]-HMPAO-SPECT normalized, 29 days later. Decreased cortical blood flow was explained by vasoconstriction following ecstasy-induced depletion of serotonin.