Gastro-oesophageal reflux disease: Medical or surgical treatment? Report of an interactive workshop

Gastroesophageal reflux disease (GERD) is the most common disease of the upper gastrointestinal tract. With the introduction of proton pump inhibitors medical treatment of GERD has been significantly improved. However, the development of laparoscopic antireflux surgery resulted in an increasing interest of surgeons in this disease. An interactive meeting was organized in order to develop an agreement between gastoenterologists and surgeons regarding therapeutic decisions and this is the main topic of this paper.     

Clinical Efficacy and Safety of the New Cardioverter Defibrillator Systems

Clinical efficacy and safety of two new third-generation implantable cardioverter defibrillators (ICD) were studied in 38 patients with ventricular tachycardia (VT) or fibrillation (VF). There were 31 patients with coronary disease, three patients with right ventricular dysplasia, one patient with dilated cardiomyopathy, and three patients with valvular disease. Twenty-four patients (group I) received an ICD with monophasic (Ventak PRx 1700, CPI) and 14 patients (group II) with biphasic shocks (Cadence V 100, Ventritex). Intraoperatively, the mean defibrillation threshold was significantly lower in group II than in group I, both in patients with induced VT (group I 11.0 ± 6.3 joules: group N 5.8 ± 1.3 joules) (P < O.01) and induced VF (group I 17.5 ± 4.6 joules; group II 9.6 ± 5.2 joules) (P < O.O1). During the mean follow-up of 12 ± 7 months four patients (11%) died. 865 arrhythmia events (AE) occurred and were terminated by ATP (671 VTs, 78%). Acceleration of VTs was observed in 28 AE (3%) and ATP was unable to interrupt 58 AE (7%). ICD shocks were delivered as a first therapy in 108 AE (13%).     

Role of Antitachycardia Pacing in Patients with Third Generation Cardioverter Defibrillators

The most effective antitachycardia pacing (ATP) mode is still a matter of debate. Randomized prospective testing of 3 different ATP modes was performed in B5 patients (pts) prior to and after cardioverter Defibrillator implantation (Ventak PHx 36 pts, Cadence V 100 29 pts). All 3 ATP modes included 4 stimulation attempts with 4–7 adaptive scanning burst pulses. Adaptive burst coupling interval was 75% in mode A, 81% in mode B and 69% in mode C. Autodecremental scanning within bursts was 8 msec in all, decremenial scanning between bursts was 8 msec in modes B and C. Each ATP mode had to be tested 3 times; all 3 ATP modes were randomly applied to each pt. During preoperative testing 91 of 133 VT episodes (68%) could be terminated by ATP. Termination was achieved in 68% with mode A, 68% with mode B and 73% with mode C, During predischarge testing, 251 VTs were induced and ATP was successful in 147 VTs (59%). Termination rate was 56% with mode A, 68% with mode B and 50% with mode C. During the mean follow-up of 12 months, 2301 arrhythmia episodes (AE) occurred. ATP was performed in 2097 AE (91%) and successful in 1920 AE (92%). Acceleration of VT occurred in 65 AE (3%) and unsuccessful ATP was observed in 112 AE (5%). It is concluded that ATP in general is highly effective in pts with sustained VT. None of the tested ATP modes, however, proved to be superior to the other.     

Assessment of the Chronotropic Response at the Anaerobic Threshold: An Objective Measure of Chronotropic Function

MEINE, M., et al. : Assessment of the Chronotropic Response at the Anaerobic Threshold: An Objective Measure of Chronotropic Function. The evaluation of the heart rate response to exercise is important for the diagnosis of chronotropic incompetence and the assessment of a rate responsive algorithm of sensorcontrolled pacemakers. The aim of the present study was to examine a classification of the chronotropic response at an individually moderate exercise level. Sixteen pacemaker patients (patient group, age 62.9 ± 7.6 years ) with sick sinus syndrome and 15 age‐matched healthy subjects (control group, age 57.6 ± 9.4 years ) underwent a maximum cardiopulmonary exercise test on a treadmill after a protocol with individually selected incremental steps. To analyze the patients' intrinsic heart rate response, the rate responsive mode of the pacemaker was switched off. Chronotropic incompetence was diagnosed in eight patients whose maximal heart rate was < 80% of the age‐predicted heart rate. The heart rate at the anaerobic threshold was significantly lower in the chronotropically incompetent subgroup than in the chronotropically competent patients and the healthy subjects (85.9 ± 6.6 beats/min vs 100.3 ± 9.9 beats/min and 112.9 ± 11.7 beats/min , respectively). The chronotropic slope of the heart rate reserve as a function of the metabolic reserve was significantly higher in the control group than in the patient groups with either mild or severe chronotropic incompetence (0.94 ± 0.17 vs 0.64 ± 0.08 and 0.43 ± 0.14 , respectively). Furthermore, the chronotropically incompetent response could be divided into a linear type with and without a threshold, an exponential, and a logarithmic type. The anaerobic threshold was an objectively detectable breakpoint at an individually moderate exercise level that could be used for characterization of chronotropic function. At the anaerobic threshold, a physiological heart rate response was about 220 ‐ age – 50 beats/min. A deviation of more than 10 beats/min below this physiological value characterized chronotropic incompetence.     

Antiarrhythmic Efficacy of Oral Sotalol in Patients with Sustained Ventricular Tachycardia or Ventricular Fibrillation Postmyocardial Infarction

In order to assess the antiarrhythmic efficacy of oral sotalol we studied 46 patients with sustained monomorphic ventricular tachycardia (n = 40) or ventricular fibrillation (n = 6) by programmed ventricular stimulation. All patients had coronary artery disease with a history of myocardial infarction. Prior to sotalol, patients were treated with a mean of 3.4 ± 1.4 antiarrhythmic Class I drugs. None of these drugs prevented sustained monomorphic ventricular tachycardia or ventricular fibrillation. During control programmed ventricular stimulation (PVS 1) ventricular fibrillation was induced in 7 patients (15%), sustained monomorphic ventricular tachycardia in 30 patients (65%), and nonsustained ventricular tachycardia in 9 patients (20%). After loading with oral sotalol (320 mg/day) programmed ventricular stimulation (PVS 2) was repeated 4.2 ± 3.3 weeks after PVS 1. Ventricular fibrillation was not inducible in any of the patients; in 10 patients (22%) sustained monomorphic ventricular tachycardia was induced, and nonsustained ventricular tachycardia was induced in 10 patients (22%). In 26 patients (57%) either no response or a short ventricular response was inducible. Our data show that oral sotalol is an effective antiarrhythmic agent in patients with sustained monomorphic ventricular tachycardia or ventricular fibrillation following myocardial infarction.     

In Vivo Depletion of Chicken T-Cell Subsets

In the chicken three types of T-cell receptors can be defined by monoclonal antibodies TCR1, TCR2 and TCR3, which recognize γδ T cells, and Vβ1- and Vβ2-expressing αβ T cells, respectively. In the present report we have analysed means of selectively depleting the γδ T cells and the Vβ1 ⁺αβ T cells. γδ cells, which represent up to 66% of all T cells in blood of a 6-month-old chicken, can be effectively depleted by neonatal thymectomy (Tx) to levels as low as 1%. Immunohistology demonstrates a similar depletion in lymphoid organs while intestinal epithelium-associated γδ T cells are affected by Tx to a lesser extent. Vβ1-bearing αβ T cells, which comprise about 80% of the αβ T cells, were depleted by embryonic and neonatal injection of the TCR2 antibody. In the thymus such treatment depleted only the Vβ1 ⁺αβ T cells with high density expression of T-cell receptor. Therefore, we thymectomized TCR2-treated animals in order to prevent development of mature Vβ1⁺αβ T cells from the low density immature thymocytes. Treatment of chickens with a total of 22 mg of TCR2 antibody plus Tx reduced Vβ⁺αβ T cells from an average of 65% to 10% of all T cells. In these TCR2 antibody-treated animals the Vβ2-expressing αβ T cells become the predominant type of T cell (average 85%).