AT occurring after CPVA plus LALA is often due to incomplete MI ablation, but may also occur at the LA roof, and ridge between the LA appendage and left PVs. Failure to achieve MI block increases the risk of developing AT. Resumption of MI conduction may also be a mechanism for AT recurrence. (PACE 2010; 460-468).

Erectile dysfunction is common in men referred for MPS, is associated with markers of adverse cardiovascular prognosis, and is an independent predictor of severe coronary heart disease and high-risk MPS findings. These results suggest that questioning about sexual function may be a useful tool for stratifying risk in individuals with suspected coronary heart disease.

Background: Survival following out-of-hospital cardiac arrest (OHCA) from ventricular fibrillation (VF) is poor and dependent on a rapid emergency response system. Improvements in emergent early response have resulted in a higher percentage of patients surviving to admission. However, the admission variables that predict both short- and long-term survival in a region with high discharge survival following OHCA require further study in order to identify survivors at subsequent highest risk. Methods: All patients with OHCA arrest in Olmsted County Minnesota between 1990 and 2000 who received defibrillation of VF by emergency services were included in the population-based study. Baseline patient admission characteristics in survivor and nonsurvivor groups were compared. Survivors to hospital discharge were prospectively followed to determine long-term survival. Results: Two hundred patients suffered a VF arrest. Of these patients, 145 (73%) survived to hospital admission (7 died within the emergency department) and 79 (40%) were subsequently discharged. Sixty-six (83%) were male, with an average age of 61.9 ± 15.9 years. Univariate predictors of in-hospital mortality included call-to-shock time (6.6 vs. 5.5 min, p = 0.002), a nonwitnessed arrest (75.4 vs. 92.4%, p = 0.008), in-field use of epinephrine (27.8 vs. 93.4%, p < 0.001), age (68.1 vs. 61.9 years, p = 0.017), hypertension (36.1 vs. 14.1%, p = 0.005), ejection fraction (32.4 vs. 42.4, p = 0.012), and use of digoxin (34.9 vs. 12.7%, p = 0.002). Of all these variables, hypertension [hazard ratio (HR) 4.0, 95% CI 1.1–14.1, p = 0.03], digoxin use (HR 4.5, 95% CI 1.3–15.6, p = 0.02), and epinephrine requirement (HR 62.0, 95% CI 15.1–254.8, p < 0.001) were multivariate predictors of in-hospital mortality. Nineteen patients (24%) had died prior to the survey follow-up. Five patients experienced a cardiac death, resulting in a 5-year expected cardiac survival of 92%. Multivariate variables predictive of long-term mortality include digoxin use (HR 3.02, 95% CI 1.80–5.06, p < 0.001), hypertension (HR 2.06, 95% CI 2.12–3.45, p = 0.006), and call-to-shock time (HR 1.18, 95% CI 1.01–1.38, p = 0.038). Conclusion: A combined police/fire/EMS defibrillation program has resulted in an increase of patients surviving to hospital admission after OHCA. This study confirms the need to decrease call-to-shock times, which influence both in-hospital and long-term mortality. This study also identifies the novel demographic variables of digoxin and hypertension, which were also independent risk factors of increased in-hospital and long-term mortality. Identification of these variables may provide utility in identifying those at high-risk of subsequent mortality after resuscitation.

Modern cardiac electrophysiology procedures include catheter-based arrhythmia ablation and transvenous device implantation, which are highly dependent on accurate, real-time cardiac imaging. With the realization that anatomic structures are critical to successful electrophysiologic procedures, accurately defining a patient's cardiac anatomy has become more important. Fluoroscopy allows for 2D imaging of cardiac structures in real-time, and is used to guide catheter and lead placement, but does not allow for visualization of soft tissues. Intracardiac echocardiography allows for both direct visualization of anatomic structures within the heart and real-time imaging during catheter placement. Despite advances in intracardiac echocardiography catheters that allow for larger windows, the ability to accurately delineate anatomic structures depends on the patient's anatomy and operator experience. Neither of these techniques allows for electrical mapping of the heart; however, both anatomic and electrical intracardiac mapping can be achieved with advanced mapping systems. These systems allow for real-time catheter localization, help elucidate cardiac anatomy, evaluate electrical activation during arrhythmias and guide catheter placement for deliverance of radiofrequency current. More recently, 3D cardiac computed tomography has been used to accurately define intracardiac anatomy; however, catheter tracking and electrical mapping cannot be performed by computed tomography. Mapping systems are now being merged with computed tomography images to produce an accurate anatomic and electrical map of the heart to guide catheter ablations. The objective of this paper is to describe the current imaging and mapping techniques used in electrophysiologic procedures.

A 24-year-old woman was referred for extraction of a single-chamber implantable cardioverter-defibrillator for persistent bacteremia. She had a severe nonischemic dilated cardiomyopathy and was in the hospital with refractory congestive heart failure. Her defibrillator had been implanted 5 months earlier for primary prevention of sudden death. A recent transesophogeal echocardiogram revealed a left ventricular (LV) ejection fraction of 0.27, but no valvular dysfunction and no pericardial effusion. In preparation for her extraction procedure, a femoral arterial line was placed, and Figure.A tracing is shown with EKG limb leads I, II, and III, and a femoral arterial pressure recording (units are mmHg). The rhythm is sinus tachycardia with a premature ventricular contraction (PVC). There are initially five sinus beats on the rhythm strip that are associated with pulsus alternans. A PVC, which is not followed by a pulse, interrupts the rhythm. The sinus beat following the PVC generates a high-amplitude pulse (asterisk), because the ventricle has had a long filling time resulting in a higher ventricular end-diastolic volume and an increase in contractility due to the Starling mechanism. After the PVC, there is augmentation of the pulsus alternans for several cycles, but the potentiation gradually dissipates. Electromechanical delay between each QRS complex and generation of the peripheral arterial pulse is also present, consistent with severe left ventricular dysfunction. the following arterial tracing was recorded (see Figure). The tracing shows augmentation of pulsus alternans after a premature ventricular contraction (PVC).After a PVC, pulsus alternans can be potentiated. 1 Due to a short filling time, the PVC generates very low stroke volume and pulse amplitude. Following the PVC, the LV has a longer filling time resulting in a higher LV end-diastolic volume and an increase in contractility due to the Starling mechanism. Thus, the beat following the PVC will generate a larger stroke volume and high-amplitude pulse. It then takes several cycles for the preload and LV contractility to return to their baseline states. Reference1. Davies LC, Francis DP, Ponikowski P, Piepoli MF, Coats AJ: Relation of heart rate and blood pressure turbulence following premature ventricular complexes to baroreflex sensitivity in chronic congestive heart failure. Am J Cardiol 2001;87:737.