Serological evidence for the association of Bartonella henselae infection with arrhythmogenic right ventricular cardiomyopathy

BACKGROUND: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an important cause of sudden death in young adults. On the basis of histopathological findings its pathogenesis may involve both a genetic origin and an inflammatory process. Bartonella henselae may cause endomyocarditis and was detected in myocardium from a young male who succumbed to sudden cardiac death. HYPOTHESIS: We hypothesized that chronic infection with Bartonella henselae could contribute to the pathogenesis of ARVC. METHODS: We investigated sera from 49 patients with ARVC for IgG antibodies to Bartonella henselae. In this study, 58 Swiss blood donors tested by the same method served as controls. RESULTS: Six patients with ARVC (12%) had positive (>1:256) IgG titres in the immunofluorescence test with Bartonella henselae. In contrast, only 1 elevated titre was found in 58 controls (p < or = 0.05). Interestingly, all patients with increased titres had no familial occurrence of ARVC. CONCLUSIONS: Further studies in larger patient cohorts seem justified to investigate a possible causal link between chronic Bartonella henselae and ARVC, in particular its sporadic (nonfamilial) form.

Frequency of spontaneous ventricular tachycardia in a pediatric population

Few data exist on the incidence of spontaneously occurring ventricular tachycardia (VT) in an unselected pediatric population. The aim of this study was to define the incidence and outcomes of VT in a general pediatric population. A retrospective analysis was performed of all documented episodes of VT in children referred to a single center during a 10-year study period ending in December 2005. The study center drains a stable referral area with 252,000 children aged <16 years, with no other pediatric cardiologic or pediatric intensive care services available. Twenty-seven patients with spontaneously occurring episodes of VT were observed, accounting for a VT incidence of 1.1 episodes/100,000 childhood years. Thirteen patients had VT in the absence of structural heart disease, and 14 had VT in the presence of a wide range of underlying cardiac disease. Overall mortality was 5 of 27 patients (19%), but mortality was seen exclusively in patients with underlying heart disease; for this subgroup of patients, mortality was 36%. Idiopathic VT in children with structurally normal hearts carried a good prognosis, and treatment was required in a minority (20%) of these patients. In conclusion, this study highlights that VT in childhood is rare, and outcomes are highly dependent on the underlying pathologic substrate.

[Arterial-adaptive dilatation and Doppler velocimetry in normal fetuses with a single umbilical artery]

PURPOSE: In this study we examined the arterial-adaptive dilatation and Doppler velocimetry, especially RI values, in normal fetuses with a single umbilical artery (SUA). MATERIALS AND METHODS: We studied 195 fetuses from 18 to 39 weeks of gestational age with a prenatally identified SUA retrospectively. They were enrolled in this study if the following information applied: > 18 weeks of gestational age, no structural or chromosomal abnormalities, and histopathological confirmation of SUA. Sonographic examination included evaluation of the umbilical artery resistance and the cross-sectional area of the umbilical cord, and its vessels were measured in all cases. Small for gestational age (SGA) was diagnosed when the birth weight was below the 10th percentile for gestational age. Fetuses with intrauterine growth restriction were defined as those with biometric data below the 5th percentile. RESULTS: There were 119 cases of prenatally identified SUA which met the inclusion criteria. RI values were below the 10th percentile in 33/119 (27.33) and below the 50th percentile in 73/119 (61.33). RI values below the 10th percentile were significantly more likely to be in the normal collective than in the growth restricted collective [31/87 (35.63%) vs. 2/32 (6.25%); p = 0.001]. Even more significant differences became apparent when comparing the RI values below the 50th percentile of both groups. An umbilical artery diameter over the 90th percentile was found in 49 (41.9%) of cases and was significantly more likely to be present in normal growing fetuses than in the growth restricted group. CONCLUSION: Normal fetuses with SUA are at higher risk to be born as SGA. With our study results we can confirm the hypothesis that Doppler flow measurements and arterial diameter in SUA are different from those found in normal fetal umbilical arteries. RI values over the 50th percentile or a cross-sectional area of the artery below 95th percentile after 26th week of gestation significantly increases the risk of SGA.

Whole body postmortem angiography with a high viscosity contrast agent solution using poly ethylene glycol as contrast agent dissolver

Postmortem minimal invasive angiography has already been implemented to support virtual autopsy examinations. An experimental approach in a porcine model to overcome an initially described artificial tissue edema artifact by using a poly ethylene glycol (PEG) containing contrast agent solution showed promising results. The present publication describes the first application of PEG in a whole corpse angiographic CT examination. A minimal invasive postmortem CT angiography was performed in a human corpse utilizing the high viscosity contrast agent solution containing 65% of PEG. Injection was carried out via the femoral artery into the aortic root in simulated cardiac output conditions. Subsequent CT scanning delivered the 3D volume data of the whole corpse. Visualization of the human arterial anatomy was excellent and the contrast agent distribution was generally limited to the arterial system as intended. As exceptions an enhancement of the brain, the left ventricular myocardium and the renal cortex became obvious. This most likely represented the stage of centralization of the blood circulation at the time of death with dilatation of the precapillary arterioles within these tissues. Especially for the brain this resulted in a distinctively improved visualization of the intracerebral structures by CT. However, the general tissue edema artifact of postmortem minimal invasive angiography examinations could be distinctively reduced.

Resuspension of the aortic valve in acute type A dissection: long-term results

BACKGROUND AND AIM OF THE STUDY: Preservation of the aortic valve during the repair of acute type A aortic dissection (AADA) is a viable option to prevent lifelong oral anticoagulation. The study aim was to assess aortic valve function following resuspension and supracoronary ascending aortic grafting. METHODS: Among a collective of 210 consecutive patients undergoing surgery for AADA, 140 (66.7%) with resuspension of the aortic valve and supracoronary ascending graft were analyzed. Of these patients, 83 (59.3%) had a complete follow up (mean 61.2 +/- 40.8 months), with 65 of the subgroup (78.3%) being followed by computed tomography scanning and echocardiography. RESULTS: Reoperation due to severe aortic valve regurgitation was required in seven patients (10.8%). The perioperative characteristics were similar in these patients; notably, no significant difference was evident with regards to the aortic annulus diameter and the severity of regurgitation at the time of surgery. The left ventricular mass index was significantly higher in patients requiring reoperation due to aortic valve regurgitation (219.3 +/- 146.6 versus 123.9 +/- 146.6 g/m2; p <0.05). None of the patients died as a result of reoperation. CONCLUSION: The long-term functional results following resuspension of the aortic valve in AADA were very good. A close echocardiographic follow up was necessary, as reoperation of the aortic valve was required in more than 10% of the collective, with an average follow up of five years. Reoperation was mainly related to secondary dilatation of the aortic root.

Percutaneous closure of a postinfarction ventricular septal defect and an iatrogenic left ventricular free-wall perforation using two Amplatzer muscular VSD occluders

A 83-year-old woman underwent percutaneous closure of postinfarction ventricular septal defect following anteroseptal myocardial infarction and percutaneous coronary intervention with stent implantation of the left anterior descending coronary artery. Postinfarction percutaneous ventricular septal defect closure was initially complicated by an iatrogenic left ventricular free-wall perforation. Both defects were closed using two Amplatzer muscular VSD occluders during the same session.

Patent foramen ovale and ventricular septal defect closure

Despite the growing recognition of the patent foramen ovale (PFO), particularly when associated with an atrial septal aneurysm, as risk factor for several disease manifestations (above all paradoxical embolism), the optimal treatment strategy for symptomatic patients remains controversial. Percutaneous PFO closure is a minimally invasive procedure which can be performed with high success and low morbidity. For secondary prevention of recurrent embolic events, it appears to be clinically at least as effective as oral anticoagulation. Ventricular septal defects (VSDs) are the most common congenital heart defects. Percutaneous VSD closure is more intricate than PFO closure. It is associated with a significant risk of both peri-interventional and mid-term complications. In suitable patients with congenital VSD, device closure may well be the preferred treatment both for muscular or perimembranous VSDs and for residual defects after surgical VSD closure. The risk of complete atrioventricular conduction block remains a concern in the perimembranous group. The history, technique and clinical role of percutaneous PFO and VSD closure are discussed, with emphasis on current problems and future developments.

Termination of Ventricular Tachycardia with Antitachycardia Pacing after Ineffective Shock Therapy in an ICD Recipient with Hypertrophic Cardiomyopathy

Implantable Cardioverter Defibrillator (ICD) implantation is the only established therapy for primary or secondary prevention of sudden cardiac death in patients with Hypertrophic Cardiomyopathy (HCM). Ineffectiveness of shock therapy for the termination of potentially fatal ventricular arrhythmias in ICD recipients is rare in the presence of appropriate arrhythmia detection by the device. We report the case of a 48-year-old woman with HCM and a single chamber ICD, who received five inefficient high-energy (35 Joules) shocks for the termination of an appropriately detected episode of Ventricular Tachycardia (VT). The episode was safely terminated with a subsequent application of Antitachycardia Pacing (ATP) by the device. At the following ICD control, an acceptable defibrillation threshold was detected.

Percutaneous left ventricular assist devices during cardiogenic shock and high-risk percutaneous coronary interventions

Left ventricular assist devices were developed to support the function of a failing left ventricle. Owing to recent technological improvements, ventricular assist devices can be placed by percutaneous implantation techniques, which offer the advantage of fast implantation in the setting of acute left ventricular failure. This article reviews the growing evidence supporting the clinical use of left ventricular assist devices. Specifically, we discuss the use of left ventricular assist devices in patients with cardiogenic shock, in patients with acute ST-elevation myocardial infarction without shock, and during high-risk percutaneous coronary interventions.

Ventricular tachycardia arising from the aortomitral continuity in structural heart disease: characteristics and therapeutic considerations for an anatomically challenging area of origin

BACKGROUND: The aortomitral continuity (AMC) has been described as a site of origin for ventricular tachycardias (VT) in structurally normal hearts. There is a paucity of data on the contribution of this region to VTs in patients with structural heart disease. METHODS AND RESULTS: Data from 550 consecutive patients undergoing catheter ablation for VT associated with structural heart disease were reviewed. Twenty-one (3.8%) had a VT involving the peri-AMC region (age, 62.7+/-11 years; median left ventricular ejection fraction, 43.6+/-17%). Structural heart disease was ischemic in 7 (33%), dilated cardiomyopathy in 10 (47.6%), and valvular cardiomyopathy in 4 (19%) patients, respectively. After 1.9+/-0.8 catheter ablation procedures (including 3 transcoronary ethanol ablations) the peri-AMC VT was not inducible in 19 patients. The remaining 2 patients underwent cryosurgical ablation. Our first catheter ablation procedure was less often successful (66.7%) for peri-AMC VTs compared with that for 246 VTs originating from the LV free wall (81.4%, P=0.03). During a mean follow-up of 1.9+/-2.1 years, 12 (57.1%) patients remained free of VT, peri-AMC VT recurred in 7 patients, and 1 patient had recurrent VT from a remote location. Three patients died. Analysis of 50 normal coronary angiograms demonstrated an early septal branch supplying the peri-AMC area in 58% of cases that is a potential target for ethanol ablation. CONCLUSIONS: VTs involving the peri-AMC region occur in patients with structural heart disease and appear to be more difficult to ablate compared with VTs originating from the free LV wall. This region provides unique challenges for radiofrequency ablation, but cryosurgery and transcoronary alcohol ablation appear feasible in some cases.