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Notes: Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy. Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is a heart muscle disease characterized by peculiar right ventricular involvement and electrical instability that precipitates ventricular arrhythmias and sudden death. The purpose of the present consensus report of the Study Group of the European Society of Cardiology and the Scientific Council on Cardiomyopathies of the World Heart Federation is to review the considerable progress in our understanding of the etiopathogenesis, morbid anatomy, and clinical presentation of ARVD/C since its first description in 1977. This article will focus on the important hut still unanswered issues, mostly regarding risk stratification, clinical outcome, and management of affected patients. Because ARVD/C is relatively uncommon and any one center may have experience with only a few patients, an international registry is being established to accumulate information and enhance the numbers of patients that can be analyzed to answer the pending questions. The registry also will facilitate pathologic, molecular, and genetics research on the etiology and pathogenesis of the disease. Furthermore, availability of an international database will enhance awareness of this largely unrecognized condition among the medical community. Physicians are encouraged to enroll patients in the International Registry of ARVD/C.

Notes: Abstract  Background and Aim: Whether the CK-MB reducing effect of ischemic preconditioning (IP) by unstable angina within 24 to 48 hours before CABG is achieved by early or by delayed preconditioning of left ventricular myocardium in humans is unknown. We investigated whether IP is associated with phosphorylation of p38 MAPK (characteristic for early preconditioning) or with increased protein expression of HSP-72 (characteristic for delayed preconditioning) at the time of CABG in patients. Methods: Nineteen patients were grouped according to the occurrence of ischemic episodes within 48 hours before CABG. The patients without angina were assigned to the control group (CON, n = 10) whereas patients who had experienced angina within 48 hours before CABG were assigned to the preconditioned group (IP, n = 9). The effect of IP on the CABG induced maximal release of creatine kinase (CK) and CK-MB was examined. Left ventricular biopsy specimens taken immediately before cross clamping from ischemic (ISCH) and from reference (REF) areas were processed to analyze p38 MAPK phosphorylation and HSP-72-protein expression. Results: While IP significantly reduced CK-MB (18.7 ± 1.3 vs. 13.8 ± 1.5 U/L, mean ± SEM, p 〈 0.05), it only tended to reduce CK (292.7 ± 32.8 vs. 274.1±31.1 U/L, p = NS, mean ± SEM). CK-MB release for any given cross-clamp time was significantly reduced by IP (regression lines: CON, y= 0.4x+ 2, r= 0.8; IP, y= 0.1x+ 10, r= 0.2; p 〈 0.01, ANCOVA). There was no effect of IP on left ventricular p38 MAPK phosphorylation. IP increased left ventricular HSP-72-protein expression in ischemic areas when compared to reference areas (1.78 ± 0.35 vs. 2.58 ± 0.65, REF vs. ISCH, PhosphorImager units ×106, mean ± SEM, p 〈 0.05, ANCOVA). Conclusions: Thus, in the human left ventricular myocardium there is a second window of protection lasting for at least 48 hours, while at that time the early phase of preconditioning has already gone.

Notes: Aim: This study investigated the value of epicardial mapping immediately before CABG in the differentiation of hibernating from scarred myocardium in correlation to the noninvasive gold standard 18F-FDG PET.Methods and Results: In 35 patients with CAD, myocardial perfusion (99mTc-Tetrofosmin-SPECT), viability (18F-FDG-PET), and function (LVangiography) were assessed before CABG. 102 bipolar epicardial electrograms per patient (n = 3570 electrograms) were recorded simultaneously with a ventricular jacket array. Based on the scintigraphic and LV angiographic data at the site of each electrode with good myocardial contact (n = 1963), segments (n = 492, 14.1 ± 5.6 per patient; mean ± SD) were classified into three groups: hibernating (n = 139), scarred (n = 104), and control (n = 249). Regional mean bipolar voltage values were calculated for Receiver Operating Characteristic (ROC) analysis. Mean bipolar voltage was significantly lower in scarred when compared to hibernating myocardium. ROC curve analysis (area under the curve of O.92 ± 0.47, mean ± SE) for mean bipolar voltage to discriminate between hibernating and scarred myocardium revealed a sensitivity of 94% with a specificity of 83% at a cut-off value of 8.75 mV.Conclusion: Hibernating myocardium can be differentiated correctly from scarred myocardium by direct epicardial mapping. In the future, hibernating myocardium may be detectable by body surface mapping techniques using inverse solutions. A.N.E. 2002;7(4):349–356

Notes: BSPM and Late Potentials in Brugada Syndrome. Introduction: The value of noninvasive markers reflecting repolarization and/or conduction abnormalities in identifying patients with abnormal ECG showing a pattern of atypical right bundle branch block and ST elevation syndrome (Brugada syndrome) at risk for life-threatening arrhythmias is controversial. Because right precordial ST elevation reflects inhomogeneous repolarization, we hypothesized that a correlation between the area of ST elevation, that is, the area of inhomogeneous repolarization, and the inducibility of ventricular tachyarrhythmias (VT) exists. Therefore, the body surface area of ST elevation and the presence of late potentials were compared to the inducibility of VT in patients with the characteristic ECG of Brugada syndrome. Methods and Results: A 120-channel body surface potential map was recorded at rest and after administration of a Class I agent (ajmaline, 1 mg/kg) to measure the body surface area of ST elevation (≥0.2 mV) in 23 individuals (16 patients had been resuscitated from near sudden cardiac death or had suffered syncope) with an ECG compatible with the diagnosis of Brugada syndrome as well as in 15 healthy controls and in 15 patients with arrhythmogenic right ventricular cardiomyopathy. Late potentials were assessed in 20 of the Brugada patients using signal-averaged ECG. Programmed ventricular stimulation was performed at two ventricular sites with up to three extrastimuli. Mean body surface area of ST elevation (≥0.2 mV) of all Brugada syndrome patients was 154 ± 139 cm2 (control 9 ± 9 cm2; P 〈 0.001). In the group of patients with arrhythmogenic right ventricular cardiomyopathy, only one patient was found to have an area of ST elevation (165 cm2). In the presence of ajmaline, area size increased to 330 ± 223 cm2 in Brugada syndrome patients (P 〈 0.05). In patients with inducible sustained (n = 15) and nonsustained VT (n = 3), a mean area of 183 ± 139 cm2 was found, whereas the area was only 52 ± 58 cm2 in those with no VT induction (P 〈 0.05). For an area ≥ 50 cm2, there were positive and negative predictive values of 92% and 60%, respectively. Positive late potentials were found in 60% of patients and correlated to the inducibility during programmed ventricular stimulation (positive predictive value 100%, negative predictive value 75%; P 〈 0.001). Conclusion: In patients with Brugada syndrome, the body surface area of ST elevation and the presence of late potentials correlate to the inducibility of VT during programmed ventricular stimulation and may be of value as a new noninvasive marker for risk stratification in these patients.

Notes: Brugada Syndrome and Supraventricular Tachyarrhythmias. Introduction: The Brugada syndrome is a distinct form of idiopathic ventricular fibrillation characterized by a unique ECG pattern consisting of a right bundle branch block-like aspect and ST segment elevation in leads V1 to V3. As a high induction rate of ventricular tachyarrhythmias has been reported in Brugada syndrome, we hypothesized that this also may be true for supraventricular tachycardias in these patients. Methods and Results: Between January 1995 and December 2000, we identified 35 consecutive patients with Brugada syndrome; 26 had a history of cardiac arrest or syncope and 9 were asymptomatic. All patients underwent electrophysiologic study, including an atrial and ventricular stimulation protocol. Ten patients (29%) were found to have supraventricular tachyarrhythmias (SVT) in addition to the Brugada syndrome. These 10 patients presented with aborted sudden cardiac death (n = 3) and/or a family history of sudden cardiac death (n = 4), syncope (n = 4), or primarily with a Brugada typical ECG, a positive family history, and palpitations (n = 2). Eight of them underwent genetic testing, but only 1 had a mutation in the SCN5A gene. In 6 patients, an AV nodal reentrant tachycardia was easily and reproducibly inducible. Two patients had clinical documented and inducible episodes of an atrial tachycardia (1 in addition to an AV nodal reentrant tachycardia). One patient had paroxysmal atrial fibrillation alternating with sinus rhythm, and 2 patients with accessory pathways were identified. Conclusion: This is the first description of an association of the Brugada syndrome with SVT. Thus, the arrhythmogenic substrate in Brugada syndrome may not be restricted to the ventricular level. Palpitations in this syndrome should raise the possibility of SVT. Conversely, in patients with SVT and aborted sudden cardiac death or syncope not related to SVT, the Brugada syndrome should be considered a possible additional electrophysiologic abnormality.

Notes: Background: Brugada syndrome is associated with a risk for sudden death, but the arrhythmic risk in an individual Brugada syndrome patient is difficult to predict. Pathologic changes in the early repolarization phase of the ventricular action potential probably constitute part of the arrhythmogenic substrate in Brugada syndrome. Microvolt T wave alternans (TWA) assesses dynamic beat-to-beat changes in repolarization and has been suggested as a marker for repolarization-related sudden death. We therefore tested whether TWA is an indicator for arrhythmias in Brugada syndrome with a focus on right precordial ECG leads. Methods: We assessed TWA in nine symptomatic, inducible patients with established Brugada syndrome and in seven healthy controls. TWA was assessed at rest and during exercise using both standard methods and an algorithm that assesses TWA in the early ST segment and the right precordial leads. Results: None of the Brugada patients developed TWA in this study irrespective of analysis at rest or during exercise, neither using standard methods nor when the early ST segment was included in the analysis. When the early ST segment was included in the analysis, nonsustained TWA was found in three out of seven, and sustained TWA in one control. Conclusion: T wave alternans is not an appropriate test to detect arrhythmic risk in patients with Brugada syndrome.

Notes: [Auszug] Arrhythmogenic right ventricular cardiomyopathy (ARVC) is associated with fibrofatty replacement of cardiac myocytes, ventricular tachyarrhythmias and sudden cardiac death. In 32 of 120 unrelated individuals with ARVC, we identified heterozygous mutations in PKP2, which encodes plakophilin-2, an ...

Notes: Variants of Preexcitation. introduction: In the present report, the electrophysiiologic findings in patients with different types of variants of preeexcitwtion, i.e., atriofascicualr, nodofacicular, and fasciculoventricular fibers, and the results of radiofrequency catheter ablation using different target sites are described. Methods and Results: Twelve patients (mean age 36 ± 17 years) with variants of the preexcitation syndromes underwent electrophysiologic study and radiofrequency catheter ablation. The atrial origin of atriofascicular pathways remote from the normal AV node was assessed by application of late atrial extrastimuli that advanced (“reset”) the timing of the next QRS complex without anterograde penetration into the AV node. In patients with atriofacicular pathways, ablation of the accessory pathway or the retrograde fast AV node pathway was attempted. Ablation of the atriofascicular pathways was guided by a stimulus-delta wave interval mapping in the first live patients and by recording of atriofascicular pathway activation potentials in the next five patients. A nodofascicular pathway was suggested if VA dissociation occurred during tachycardia and if atrial extrastimuli failed to reset the tachycardia without anterograde penetration into the AV node. A fasciculoventricular connection was suggested if the proximal insertion of the accessory pathway was found to arise from the His bundle or bundle branches. The PR interval was expected within normal limits during sinus rhythm and the QRS complex to he slightly prolonged with a discrete slurring of the R wave, suggesting a small delta wave. Ten of the 12 patients had evidence for atriofascicular pathways and one patient each for a nodofascicular and fasciculoventricular pathway. In six patients, the atriofascicular pathways were successfully ablated, and in two patients, the retrograde fast AV node pathway. In one patient, a concealed right posteroseptal accessory AV pathway served as the retrograde limb and was successfully ablated. The nodofascicular pathway was shown to he a bystander during AV node reentrant tachycardia. After successful fast AV node pathway ablation resulting in marked PR prolongation, no preexcitation was present during sinus rhythm because of the proximal insertion of the nodofascicular pathway distal to the delay producing parts of the AV node. The proximal insertion of the fasciculoventricular pathway was suggested to arise distal to the AV node at the site of the penetrating AV bundle. The earliest ventricular activation at the His-bundle recording site indicated the ventricular insertion of this accessory connection into the ventricular summit. The fasciculoventricular connection gave rise to a fixed ventricular preexcitation and served as a bystander during orthodromic AV reentrant tachycardia incorporating a left-sided accessory AV pathway.

Notes: Ablation with Temperature-Controlled 5-French Catheters. Introduction: In the present study, we assessed the feasibility of radiofrequency (RF) ablation of accessory pathways and AV nodal reentrant tachycardias with novel 5-French catheters with 4-mm tip electrodes using established mapping criteria and temperature-controlled power output control. Methods and Results: In this prospective study, 60 consecutive adult patients (mean age 36 ± 20 years) with accessory pathways (n = 37; 24 left-sided) or AV nodal reentrant tachycardia (n = 23) underwent RF catheter ablation. A 5-French catheter with a 4-mm tip electrode and an embedded thermistor was used for RF application. The surface of the tip electrodes was 26 mm2 compared to 38 mm2 of 7-French catheters with 4-mm tip electrodes from the same catheter series. Power output was automatically and continuously adjusted according to the preset catheter tip temperature of 60° to 70°C. Pulse duration was 90 seconds. For left-sided accessory pathways, the retrograde route via the femoral artery was used. After removing the 5-French sheaths, only 4 hours of bed rest were advised. For ablation of AV nodal reentrant tachycardia, the so-called slow pathway was targeted for ablation. Acute success was achieved in 34 (92%) of 37 patients with accessory pathways and 23 (100%) of 23 patients with AV nodal reentrant tachycardia. A mean of 3 ± 4 RF pulses (median 2 pulses; range 1 to 20 pulses) was applied. The mean fluoroscopy time was 26 ± 21 minutes. No complete AV block or other procedure-related complications were observed. Recurrences occurred in 2 patients with accessory pathways and in 2 patients with AV nodal reentrant tachycardia during a follow-up of 9 ± 4 months. Conclusions: Temperature-controlled RF ablation of accessory pathways and AV nodal reentrant tachycardia in adults using 5-French catheters is feasible, effective, and safe. Ablation with 5-French catheters might help to reduce the complication rate of catheter ablation techniques.

Notes: Abstract. In clinical and research studies, images obtained using carrier-added meta-[123I]iodobenzylguanidine (c.a. [123I]MIBG) have shown quite variable quality, with varying levels of uptake in lung, liver and mediastinum; this is a significant problem for quantification of the myocardial uptake by means of region ratios. First experimental and preliminary human data in respect of no-carrier-added (n.c.a.) [123I]MIBG are indicative of improved imaging quality. The aim of the present study was to evaluate the clinical value of myocardial scintigraphy with n.c.a. [123I]MIBG in patients with tachyarrhythmias. The study population comprised 24 patients with tachyarrhythmogenic diseases routinely studied by cardiac single-photon emission tomography (SPET) with [123I]MIBG. Twelve of the 24 patients were studied with c.a. [123I]MIBG (seven females and five males; mean age 42±13 years, range 20–60 years), whereas the other 12 were studied with n.c.a. [123I]MIBG (ten females, two males; mean age 41±11 years, range 18–60 years, P=NS). For quantification of the specific uptake in the different organs, count ratios were calculated on SPET images acquired 4 h p.i. Visual analysis of all [123I]MIBG scans showed improved image quality (improved contrast between heart and neighbouring organs) in n.c.a. studies as compared with c.a. studies. A significantly higher heart/left atrial blood ratio was found in the n.c.a. studies as compared with the c.a. studies (10.3±3.2 vs 5.3±1.3, P=0.0003); furthermore, significantly higher heart/lung and heart/liver ratios (2.5±0.6 vs 1.5±0.3, P=0.0002, and 0.8±0.2 vs 0.6±0.1, P=0.0006, respectively) were obtained in the c.a. studies, whereas lung/left atrial blood and liver/left atrial blood ratios showed no significant differences (4.2±1.3 vs 3.6±1.1, P=0.39, and 13.7±5.2 vs 9.6±2.2, P=0.21, respectively). In conclusion, the use of n.c.a. [123I]MIBG yields a significantly higher myocardial uptake associated with improvement in contrast between the heart and neighbouring organs and is therefore superior to the commercially available c.a. [123I]MIBG for use in clinical and research studies of the myocardial presynaptic sympathetic nervous system. Furthermore, our data indicate that for quantification the use of a left atrial blood reference region of interest, which is only available on SPET studies, is to be recommended.