Author/Editor		Černe, Andreja; Zupan, Igor; Ramovž, Andrej
Title		Dual-chamber pacing in a patient with left ventricular outflow tract obstruction
Translated title		Dvo-komorna elektrostimulacija srca pri bolnici z obstrukcijo v iztočnem traktu levega prekata
Type		članek
Source		Slov Kardiol
Vol. and No.		Letnik 3, št. 2
Publication year		2006
Volume		str. 168-71
Language		eng
Abstract		Atrioventricular (AV) synchronous pacing with a short AV delay affects the left ventricular depolarization pattern and may reduce the pressure gradient in the left ventricular outflow tract (LVOT). A case is presented of a 65-year-old woman with obstructive hypertrophic cardiomyopathy (HOCM) and concomitant complete AV block who was admitted to our hospital due to dyspnea, palpitations and presyncope on exertion. Echocardiography showed asymmetric hypertrophy of the interventricular septum, systolic anterior motion of the mitral valve and moderate mitral regurgitation. The LVOT pressure gradient (PG), measured using continuous wave Doppler recording, was 90 mmHg. Due to the complete AV block, the implantation of a permanent DDDR pacemaker with a short AV delay was indicated. A significant reduction in LVOT obstruction was demonstrated after 48 hours (PG = 20 mmHg) and an almost complete restoration of gradient (PG = 61 mmHg) was shown immediately after the DDDR was turned off. The echocardiogram also showed disappearance of the systolic anterior motion of the mitral valve and regression of mitral regurgitation. After four months of permanent pacing, the LVOT gradient remained low (PG = 26 mmHg). The patient experienced a considerable improvement in symptoms and could resume normal activities. In conclusion, DDDR pacing effectively reduced LVOT obstruction and relieved symptoms in our patient with HOCM. Thus, dual-chamber pacing should be considered as an effective therapeutic option in patients with HOCM.
Summary		Sekvenčna elelctrostimulacija srca s kratkim atrioventrikularnim (AV) intervalom spremeni potek depolarizacije levega prekata in lahko zmanjša razliko tlakov v iztočnem traktu levega prekata (LVOT). Prispevek prikazuje primer 65-letne bolnice z obstruktivno hipertrofično kardiomiopatijo (HOCM) in sočasnim popolnim AV blokom, ki je bila obravnavana na naši kliniki zaradi dušenja, palpitacij in presinkope med naporom. Z ultrazvočno preiskavo srca smo prikazali asimetrično hipertrofijo medprekatnega pretina, anteriorni pomik sprednjega lističa mitralne zaklopke v sistoli in zmerno insuficienco mitratne zaklopke. S kontinuirano dopplersko preisicavo smo izmerili razliko tlakov (pressure gradient, PG) v LVOT 90 mmHg. Zaradi popolnega AV bloka smo bolnici vstavili trajni srčni spodbujevalnilc tipa DDDR in nastavili kratek AV interval. Po 48 urah smo ugotovili pomembno zmanjšanje obstrukcije pretoka v LVOT (PG = 20 mmHg), izginotje anteriornega pomika sprednjega lističa mitralne zaktopke v sistoli in zmanjšanje insuficience mitralne zaklopke. Akutni učinek elektrostimulacije srca na zmanjšanje obstrukcije v LVOT smo potrdili s prehodno prekinitvijo delovanja DDDR, po čemer se je razlika tlakov v LVOT skoraj v celoti povrnila na izhodiščno vrednost (PG = 61 mmHg). Ob kontrolnem pregtedu po štirih mesecih trajne elektrostimulacije srca smo ugotovili vztrajajočo nizko obstrukcijo v LVOT (PG = 26 mmHg). Bolnica je navajala pomembno izboljšanje kliničnih simptomov in je bila normalno telesno zmogljiva. Zaključujemo, da je pri bolnici z obstrukcijo v LVOT in sočasnim popolnim AV blokom elektrostimulacija srca DDDR pomembno zmanjšala razlilko tlakov v LVOT in odpravila simptome. Dvokomorna elektrostimulacija je lahko učinkovit način zdravljenja bolnikov s HOCM.
Descriptors		VENTRICULAR OUTFLOW OBSTRUCTION CARDIOMYOPATHY, HYPERTROPHIC CARDIAC PACING, ARTIFICIAL ELECTROCARDIOGRAPHY ECHOCARDIOGRAPHY, DOPPLER MIDDLE AGE HEART BLOCK