Asunto(s)
Terapia de Resincronización Cardíaca/métodos , Desfibriladores Implantables , Hemodinámica/fisiología , Contracción Miocárdica/fisiología , Gasto Cardíaco/fisiología , Cardiomiopatías/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Disfunción Ventricular Izquierda/fisiopatología , Disfunción Ventricular Izquierda/terapiaRESUMEN
BACKGROUND: The Quartet quadripolar lead (St. Jude Medical Inc., St. Paul, MN, USA) offers 10 different left ventricle pacing configurations that may further influence hemodynamic parameters compared to traditional bipolar pacing configurations. The purpose of this study was to evaluate whether pacing from additional quadripolar lead vectors could enhance cardiac output (CO). METHODS: For each patient, CO was measured in "no-pacing" and in all the 10 configurations available, within 7 days of implantation of the device. Tip-ring, tip-right ventricular coil (RVC), and ring-RVC vectors were considered as traditional vectors. The seven additional configurations available in the quadripolar lead were considered as nontraditional vectors. CO was measured by ECHO. The best configuration was defined as the one presenting the highest CO measurement within configurations, which have a capture threshold <3 V and a safety margin between the capture and the phrenic nerve stimulation thresholds. RESULTS: Fifty-one standard cardiac resynchronization therapy patients were enrolled. The mean of each patient's best CO obtained with traditional vectors was higher than the baseline nonpaced CO (4.16 L/min vs 3.64 L/min). The mean of each patient's best CO, including all 10 available configurations, was also higher than the baseline nonpaced CO (4.33 L/min vs 3.64 L/min). In addition, the mean of each patient's best CO obtained with the best configuration available through a quadripolar lead was better than the mean of each patient's best CO obtained with a traditional configuration. In 53% of patients, the best CO was obtained with a nontraditional vector unique to the quadripolar lead. CONCLUSIONS: A quadripolar lead offers multiple additional pacing options to increase CO acutely compared to conventional bipolar leads.
Asunto(s)
Gasto Cardíaco , Dispositivos de Terapia de Resincronización Cardíaca , Electrodos Implantados , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/prevención & control , Disfunción Ventricular Izquierda/diagnóstico , Disfunción Ventricular Izquierda/prevención & control , Adulto , Anciano , Diseño de Equipo , Análisis de Falla de Equipo , Femenino , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Resultado del Tratamiento , Disfunción Ventricular Izquierda/fisiopatologíaRESUMEN
Pacemaker manufacturers have developed new algorithms to preserve intrinsic conduction in order to reduce unnecessary stimulation and looking for physiological pacing. This case report highlights some of the new challenges related to these algorithms which include possible ECG misinterpretations and inaccurate programming leading to potential negative consequences.
