A comparison of the acute and long-term hemodynamic effects of ventricular inhibited and atrial synchronous ventricular inhibited pacing.

Abstract

SUMMARY Sixteen patients treated with a noninvasively programmable pacemaker were examiined after a prolonged period of ventricular inhibited (VVI) and atrial synchronous ventricular inhibited (VDD) pacing. Maximal working, capacity was determined by bicycle ergometry. Atrial and ventricular rates, brachial artery cuff pressure and breathing rate were determined at rest and during exercise. There was a mean increase in working capacity of 24% with VDD compared with VVI pacing (p < 0.001). Thirteen of the patients were catheterized. During VDD pacing, cardiac output was significantly higher, particularly during exercise (i 32%) due to the capability of heart rate increase and despite a substantial compensatory stroke volume increase during VVI pacing. Arteriovenous oxygen difference was much higher during VVI pacing, reaching 164 14 mi/I during the highest work load, while the corresponding level during VDD pacing was 140 ± 14 ml/l (p < 0.001). During exercise, arterial blood lactate was significantly higher during VVI than during VDD pacing. Heart size was significantly smaller, 568 ± 98 vs 530 96 ml/m2 BSA (p < 0.05), during VDD pacing. A questionnaire was completed by the patients to evaluate subjective symptoms and pacemaker preference. This part of the study favored the VDD mode of pacing. maker exchange. The VDD pacemaker we described' can be programmed noninvasively to either the VVI or the VDD mode, permitting comparisons of prolonged periods of pacing in either mode.The aim of the present study was to compare the acute and chronic hemodynamic performance at rest and during exercise with VVI and VDD pacing and to study the maximal exercise capacity after a prolonged period of VVI and VDD pacing. Material and Methods PatientsSixteen patients treated with a VDD pacemaker gave informed consent to the study. Thirteen of the patients participated in the complete study and three agreed to the noninvasive part only (patients 9, 14 and 15). Selected data from the patients are presented in table 1. The PacemakerThe pacemaker (Medtronic 2409) has been described in detail.9 Briefly, it is a VDD unit with a ventricular escape rate variable from 50-80 beats/min and a maximum atrial synchronous rate variable from 100-175 beats/min. These rates can be noninvasively programmed. When the backup rate is programmed, the mode is also programmed to VVI at the selected rate. Programming the upper rate limit simultaneously programs the mode to VDD without changing the previously programmed backup rate. ProcedureThe study started with a period of pacing planned to last at least 3 months. During this period, patients 1-9 846 by guest on May 9, 2018 http://circ.ahajournals.org/ Downloaded from

Atrioventricular pacemaker. Incidence and causes of reprogramming in long-term follow-up

“…In addition, the complication rates attributed to the most sophisticated systems have been considered high and of difficult management, particularly for the nonspecialized physician [3][4][5][6] . Several studies have shown the clinical and hemodynamic advantages of the DDD,C mode stimulation as compared with the VVI,C mode, both for total atrioventricular block and sick sinus syndrome 4,6,10,14,15 . The VVI,C pacemaker has been associated with a lower physical capacity 4,15 , a worse quality of life 6,10,15 , an enlargement of the cardiac silhouette 14 , the pacemaker syndrome 16 , and a higher mortality rate 17 .…”

“…Other studies have shown no significant difference in regard to mortality 3 or functional capacity 5 . Atrioventricular resynchronization, considered responsible for improving physical capacity by some authors 4,14 , was challenged by Chu-Pak Lau et al 18 , who attributed this increment basically to variations in heart rate.…”

Rate adaptive pacing in patients with chronotropic incompetence - Therapy

“…Während die hämodynamische Überlegen-heit der vorhofgesteuerten (DDD-/VDD-) gegenüber der festfrequenten Ventrikelstimulation (VVI) im Langzeitverlauf belegt ist (2,6,11,14,15) …”

"Contribuição ao estudo da estimulação ventricular e do atrio ventricular universal em portadores da miocardiopatia chagásica: avaliação clínica e hemodinâmica em repuso e exercício"

“…) KRUSE & RYDÉN, 1981;KRUSE et al, 1982;PEHRSSON, 1983;PERRINS et al, 1983;KRISTENSSON et al, 1985a;KRISTENSSON et al, 1985b, em estudos clínicos pareados, relataram a melhora da capacidade física dos pacientes, de 13 a 22%, com a mudança da estimulação ventricular para atrioventricular. KARLÖF, 1974;KAPPENBERGER et al, 1982;KRUSE et al, 1982;PEHRSSON & ASTRÖM, 1983e NORDLANDER et al, 1987 As principais desvantagens da estimulação atrioventricular universal são: presença de dois eletrodos intravasculares; maior tempo cirúrgico; menor duração da bateria do gerador de pulsos, devido ao maior consumo de energia e custo (cerca de 40% maior que os sistemas ventriculares). (DODINOT & KUBLER, 1982;KRISTENSSON et al, 1984).…”

“…(FRANCIOSA et al, 1981;WEINER, 1983;BUGNI 1984;FRANCIOSA, 1984;WEBER et al, 1984a;WEBER et al, 1984b. ) Com o objetivo de estudar comparativamente modos de estimulação cardíaca artificial, o estudo hemodinâmico tem sido empregado isoladamente (SAMET et al, 1966;SAMET et al, 1968;LEINBACH et al, 1969;FANANAPAZIR et al, 1983), ou associado ao exercício (KARLÖF, 1974;KAPPENBERGER et al, 1982;KRUSE et al, 1982;PEHRSSON & ASTRÖM, 1983).…”