Ventricular pacing triggered by atrial oesophageal wave: A new physiological temporary pacing mode during acute myocardial infarction complicated by 3rd degree AV block and low cardiac index

Acute myocardial infarction (AMI), complicated by advanced AV block, often produces life-threathening haemodynamic changes. VDD, rather than VVI pacing, preserving atrial contribution, can improve haemodynamics, but it requires two intracavitary catheters; moreover, the displacement of atrial lead is frequent. In 15 patients (nine men, six women, mean age 65 ± 6 years), without sinus node dysfunction, with AMI (10 anterior, five inferior), advanced AV block and low cardiac index (CI), AV synchronism was restored with a temporary bipolar right ventricular USCI 6F catheter, and a Medico Toec 4 oesophageal tetrapolar catheter. Atrial waves with amplitude <0.5 mV were filtered (50-70 Hz) and amplified through a proper device. The mean bipolar atrial wave amplitude recorded was 1.1 ± 0.5 mV. In all patients we obtained a constant VDD pacing for a mean period of 28.7 ± 27 h (4-82 h) without pacing malfunctions. The mean increasing of CI was +20%. The oesophageal lead was well tolerated in all patients and liquid and food ingestion was allowed. This technique requires only one intravenous lead (with reduced risks of infections, phlebothrombosis, thromboembolism, cardiac rupture), reduces sensing defects, frequent with atrial lead and is an easy, rapid, safe method for temporary physiological pacing.