Dragutin Savic

Permanent Endovenous Pediatric Pacing: Absence of Lead Failure—20 Years Follow‐Up Study

Background: The aim of the study was to analyze endovenous pacing lead survival in pediatric population implanted by cephalic cut down, or by axillary vein puncture.

Association between stimulated QT interval and ventricular rhythm disturbances: influence of autonomic nervous system.

To examine the association between ventricular rhythm disturbances and changes in the pacemaker‐induced stimulated T interval (STIM‐T interval), we compared findings from monitoring of two patient groups. The first group consisted of 15 patients with QTX microprocessor pacemakers and the second group consisted of 198 patients with documented ventricular rhythm disturbances and coronary artery disease (CAD). In the first group, which was free of ventricular rhythm disturbances and manifest coronary artery disease, the STIM‐T interval was measured every 4 hours over a 36‐hour period at four pacemaker frequency settings (70, 80, 90, and 100) in order to observe the circadian variation of the STIM‐T interval as a function of changes in autonomic nervous system (ANS) tone. The second group was comprised of patients with CAD and over 30 VES/hrs (Lown grade classification 1–5), and taking no antiarrhythmic medication. These patients were followed using 24‐hour Holter monitoring over a minimum of 23 hours and with less than 5% artifact/recording. Information regarding mean hourly heart rate, total number of VES, VES pairs, VT runs, and ischemic episodes in this group was compared with changes in the STIM‐T interval in the first group. The STIM‐T interval was found to be shorter during the day and longer at night at all heart rate settings. The total frequency of VES, of VES pairs, VT runs, and ischemic episodes in the second group varies in a similar circadian fashion. The greatest total number of VES, of VES pairs, VT runs, and ischemic episodes was recorded in the waking hours, at the same time when the STIM‐T interval is the shortest, while this number was significantly lower during sleep, when the STIM‐T interval of the first group is the longest. This coincidence of circadian variation pattern between STIM‐T interval in group I, and ventricular arrhythmias and ischemic episodes in group II, suggests that alterations in ANS tone reflected in the STIM‐T interval may be an important factor in the occurrence of these untoward events.

Minithoracotomy as the primary alternative for left ventricular lead implantation during cardiac resynchronization therapy: Can the cardiac surgeon reduce the number of nonresponders

Svetozar PUTNIK Departement of Cardiac Surgery Clinical Centre of Serbia Koste Todorovića 8 11000 Belgrade, Serbia svetozar073@yahoo.com SUMMARY Introduction/Objective Numerous anomalies of the cardiac venous system prevent the optimal endovascular implantation of the left ventricular (LV) lead in more than 15% of patients with indication for cardiac resynchronization therapy (CRT). The endovenous approach in these patients can be one of the potential reasons for the large number of nonresponders reported in the literature. The purpose of this study was to analyze the results of an alternative myoepicardial approach to the stimulation of the left ventricle in CRT. Methods From June 2014 to December 2015 at the Department of Cardiac Surgery of the Clinical Centre of Serbia, 15 myoepicardial LV leads for CRT were implanted. Coronary sinus venography revealed thrombosis of the coronary sinus in nine patients, and unfavorable anatomy of the coronary venous system in six patients. In all patients, limited left thoracotomy was used as an approach to the lateral wall of the heart. Results There were no major surgical complications and no lethal hospital outcomes. In a six-month follow-up period we registered a significant increase in the length of the six-minute walk test (for an average of 57.9 m), reduction of the QRS complex width (to 26.25 ms), increase in left ventricular ejection fraction (12.2%), and reduction of mitral regurgitation for 1+. Based on all the parameters, it was concluded that all patients responded favorably to the applied CRT. Conclusion Closer cooperation between cardiologists and cardiac surgeons in identifying patients who would benefit the most from a myoepicardial approach for LV stimulation is necessary in order to attempt to reduce the nonresponder rate.

Low incidence of complications after cephalic vein cutdown for pacemaker lead implantation in children weighing less than 10 kilograms: A single-center experience with long-term follow-up

BACKGROUND Only a few studies on the cephalic vein cutdown technique for pacemaker lead implantation in children weighing ≤10 kg have been reported even though the procedure is widely accepted in adults. OBJECTIVE The purpose of this study was to prove that cephalic vein cutdown for pacemaker lead implantation is a reliable technique with a low incidence of complications in children weighing ≤10 kg. METHODS The study included 44 children weighing ≤10 kg with an endocardial pacemaker. Cephalic, subclavian, and axillary vein diameters were measured by ultrasound before implantation. The measured diameters were used to select either an endocardial or epicardial surgical technique. Regular 6-month follow-up visits included pacemaker interrogation and clinical and ultrasound examinations. RESULTS Two dual-chamber and 42 single-chamber pacemakers were implanted. Mean weight at implantation was 6.24 kg (range 2.25-10.40 kg), and mean age was 11.4 months (range 1 day-47 months). In 40 children (90.1%), the ventricular leads were implanted using the cephalic vein cutdown technique, and implantation was accomplished via the prepared right external jugular vein in 4 of the children (9.9%). The atrial leads were implanted using axillary vein puncture and external jugular vein preparations. Mean follow-up was 8.9 years (range 0-20.9 years). Only 1 pacemaker-related complication was detected (a lead fracture near the connector that was successfully resolved using a lead repair kit). CONCLUSION The cephalic vein cutdown technique is feasible and reliable in children weighing ≤10 kg, which justifies the application of additional surgical effort in the treatment of these small patients.

Ascending aorta false aneurysm as a late complication of aortic valve surgery

INTRODUCTION False aneurysms of the ascending aorta represent a rare but potentially fatal complication of cardiac surgical procedures. Predisposing factors are aortic dissection, infection, connective tissue disorders, chronic hypertension, aortic calcifications and aortotomy dehiscence. At the beginning they are usually asymptomatic, but later various symptoms arise as a consequence of vital structures compression. Potential risk of rupture rises with time and pseudoaneurysm enlargement. From surgical point of view treatment of such cases represents a unique challenge because of the great danger of inadvertent opening of the aneurysm during resternotomy. CASE OUTLINE A 58-year-old female patient underwent aortic valve replacement due to severe aortic stenosis in 2004. Operation and postoperative recovery were uneventful.Three years later she started complaining about chest pain. On chest X-ray there was upper mediastinal widening. CT scan showed a pseudoaneurysm of the ascending aorta located in front of the right atrium and right ventricle, which was subsequently verified by angiography. During redo operation the pseudoaneurysm was successfully resected and aorta closed with separate ethybond sutures with pledgets. CONCLUSION Postoperative pseudoaneurysms of the ascending aorta mostly arise from the suture lines. The most useful diagnostic procedures are contrast CT scan, echocardiography, angiography and MRI. Surgical intervention is absolutely indicated. The institution of cardiopulmonary bypass by alternative ways before chest opening is strongly recommended.