Indications for Pericardial Glutaraldehyde-Preserved Xenograft in Repair of Congenital Heart Disease

A glutaraldehyde-preserved equine pericardial xenograft was implanted in 370 patients between 1981 and 1987; pericardial sac closure in 320 (mainly over Dacron implants), atrial repairs in 19, arterial reconstructions in 22 (right outflow tract in 19, Konno's procedure in three), control of bleeding after surgery for thoracic aneurysms in seven, control of plasma leaking PTFE graft in one, and repair of diaphragmal agenesia in one. Overall infection rate was 3/370 (0.8%). Epicardial adhesions (12) at reoperation for orthotopical implants were graded 1.3 +/- 0.9 on a scale of 6 (0 = no adhesions, 5 = calcified or ossified adhesions) after 4 +/- 2 months. Shrinkage of xenograft occurred in 3/19 (16%) atrial repairs and lesser degree aneurysmal dilatation appeared in 1/19 (5%) reconstructions of the right outflow tract. No complications occurred in the implants without direct exposure to the blood stream. We recommend pericardial xenograft for Konno's procedure and control of bleeding. It should not be used routinely in the low pressure side.     

Sleep onset and cardiovascular activity in primary insomnia

The transition from wakefulness to sleep is characterized typically by a shift from sympathetic to parasympathetic regulation. Physiological functions, depending on the neurovegetative system, decrease overall. Previous studies have shown cardiovascular and electroencephalographic hyperactivity during wakefulness and sleep in insomniacs compared with normal sleepers, but there is very little evidence of this in the process of sleep onset. The purpose of this study was to compare cardiovascular and autonomic responses before and after falling asleep in eight insomniacs (who met DSM‐IV criteria for primary insomnia) and eight normal sleepers. Non‐invasive measures of heart rate (HR), stroke volume (SV), cardiac output (CO) and pre‐ejection period (PEP) were collected by impedance cardiography during a night of polysomnographic recording. Frequency domain measures [low‐frequency (LF), high‐frequency (HF)] of heart rate variability (HRV) were also estimated. Decrements in HR and CO and increases in SV and HF normalized units (n.u.) were found in both groups after sleep onset compared with wakefulness. Conversely, PEP (related inversely to sympathetic β‐adrenergic activity) showed increases after sleep onset in controls, but remained unchanged in insomniacs. PEP was also significantly lower in insomniacs than in normal sleepers in both conditions. These data suggest that, whereas normal sleepers follow the expected progressive autonomic drop, constant sympathetic hyperactivation is detected in insomniacs. These results support the aetiological hypothesis of physiological hyperarousal underlying primary insomnia.     

Left Ventricular Perforation During Percutaneous Balloon Mitral Valvuloplasty With Emergency Surgery

Two cases of left ventricular (LV) perforation by balloon catheter following successful balloon mitral valvuloplasty are presented. The first patient was dilated first with a single straight-tip balloon catheter and after with a double balloon catheter. The second patient underwent a valvuloplasty with a double balloon catheter only. The subsequent tamponade was treated by immediate aspiration but without hemodynamic improvement. Both patients required emergency surgery with surgical repair of the LV apex, and both of them could be weaned. Both patients are well 18 months after the procedure. We discuss the mechanism of this serious complication and technical considerations to prevent it.     

Slow Pathway Radiofrequency Ablation in Patients with AVNRT: Junctional Rhythm is Less Frequent during Magnetic Navigation Ablation Than with the Conventional Technique

Introduction: The occurrence of accelerated junctional rhythm (JR) during radiofrequency ablation of the slow pathway in patients with atrioventricular nodal reentrant tachycardia (AVNRT) is frequent. The aim of the present study was to compare the occurrence of JR during magnetic remote catheter ablation to the conventional manual ablation.
Methods and Results: Twenty six patients (males: seven; age: 51 ± 15 years) underwent slow pathway ablation with magnetic navigation (MN) system (Niobe, Stereotaxis Inc., St. Louis, MO, USA) and were compared to a control group of 11 patients (males: three; age: 53 ± 16 years) treated with conventional manual ablation. A 4-mm nonirrigated tip catheter was used in both groups with a maximum of 30 W and 60°C. Acute success was obtained in all patients. In the MN group, three patients out of 24 had no junctional beat (JB) at all and seven patients had 10 or less JB. In contrast, in the conventional group no patient had less than 10 JB. The mean number of JB in the MN group was 66 ± 94.9 (0–410) and 200 ± 243.1 (43–914) in the control group (P = 0.019). In the MN group one patient had a first-degree atrioventricular block. No other complication occurred.
Conclusions: Magnetic remote catheter ablation of AVNRT is effective and is associated with less JB than the manual conventional technique. Therefore, JB may not be considered as a mandatory indicator for successful AVNRT ablation with MN system. (PACE 2010; 11–15)