Non-invasive determination of the optimized atrioventricular delay in patients with implanted biventricular pacing devices.

BACKGROUND: Biventricular (BiV) is extensively used in the treatment of congestive heart failure but so far no recommendations for optimized programming of atrioventricular-delay (AVD) settings have been proposed. Can AVD optimization be performed using a simple formula based on non-invasive doppler-echocardiography? METHODS: 25 patients (ejection fraction 30+/-8%) received BiV ICDs. Doppler-echocardiographic evaluation of diastolic and systolic flow was performed for different AVDs (30ms to 150ms) and different stimulation sites (left ventricular (LV), right ventricular and BiV). The optimal atrioventricular delay was calculated applying a simple formula based on systolic and diastolic mechanical delays determined during doppler-echocardiography. RESULTS: The mean optimal AVD was calculated to be 112+/-29ms (50 to 180ms) for BiV, 95+/-30ms (65 to 150ms) for LV and 75+/-28ms (40 to 125ms) for right ventricular pacing with wide interindividual variations. Compared to suboptimal AVDs diastolic optimization improved preejection and ejection intervals independent to pacing site. Optimization of the AVD significantly increased ejection time during BiV pacing (279ms versus 266ms; p<0.05). Compared to LV or right ventricular pacing BiV pacing produced the shortest mean pre-ejection and longest ejection intervals as parameters of improved systolic ventricular contractile synchrony. Diastolic filling times were longest during BiV pacing compared to LV or RV pacing. CONCLUSIONS: Individual programming of BiV pacing devices increases hemodynamic benefit when implementing the inter-individually widely varying electromechanical delays. Optimization applying a simple formula not only improves diastolic ventricular filling but also increases systolic functional parameters.

Clinical and angiographic results of coronary artery stenting using PURA-VARIO (PUVA) stents.

BACKGROUND: Many different stent types are available for intracoronary placement. No clinical trial has demonstrated clearly the superiority of any stent design over another. METHODS: This study was designed to analyze clinical and angiographic results after using intracoronary PURA-VARIO (Devon Medical, Hamburg, Germany) (PUVA) stents. A total of 306 implanted stents were investigated in a series of 217 unselected patients (61.2 +/- 10.7 years, 74.3% male). Stenting was performed electively and during acute coronary syndromes. Stents were manually mounted on angioplasty balloons and expanded in the target lesion. Angiographic measurements were carried out by quantitative coronary angiography. RESULTS: Stenting was successful in 214/217 patients (98.8%). During hospitalization (median three days) 206 patients (94.9%) were free from adverse cardiac events. Stent thrombosis occurred in five patients (2.3%), Q-wave infarction in one (0.5%) and urgent percutaneous target vessel revascularization in four (1.8%). Follow-up angiography, performed in 170 patients (78.3%) showed a restenosis (>/=50% diameter stenosis) in 44/170 patients (25.9%), requiring angioplasty in 29 (17.2%). A surgical revascularization was recommended in 13 patients (7.6%). One patient died during follow-up from an unknown cause; however, sudden cardiac death was most likely. CONCLUSIONS: PUVA stents are characterized by a high level of safety and efficacy. Clinical and angiographic results are comparable with those of other approved stents.

Left atrial versus bi-atrial Maze operation using intraoperatively cooled-tip radiofrequency ablation in patients undergoing open-heart surgery: safety and efficacy.

OBJECTIVES: We sought to determine whether limited left atrial Maze surgery encircling each of the pulmonary veins, using cooled-tip radiofrequency (RF) ablation, is as effective as the bi-atrial approach? BACKGROUND: The original Cox/Maze operation effectively restores sinus rhythm (SR) in patients with atrial fibrillation (AF). Ablation procedures aimed at eliminating pulmonary vein foci have produced promising short-term success. METHODS: This was a prospective analysis of patients with chronic AF undergoing open-heart surgery in addition to the Maze operation, using intraoperatively cooled-tip RF ablation either in the left atrium alone (group A) or in both atria (group B). RESULTS: Patients in group A (n = 21) and group B (n = 49) did not differ in terms of their baseline characteristics. Concomitant open-heart surgical procedures included mitral valve replacement (3 vs. 25), mitral valve plasty (0 vs. 2), mitral and aortic valve replacement (1 vs. 1), aortic valve replacement (4 vs. 6) and coronary artery bypass grafting (13 vs. 15) in groups A and B, respectively. Follow-up ranged from 1 to 50 months. The overall cumulative rates of SR were 82% in group A and 75% in group B, without a statistically significant difference (p = 0.571). Bi-atrial contraction was revealed in 92.3% of patients in SR in group A and in 79.2% in group B. The cumulative survival rates were 90.5% in group A and 77.9% in group B (p = 0.880). CONCLUSIONS: A left or bi-atrial Maze operation using intraoperatively cooled-tip RF ablation can safely be combined with open-heart surgery. A left atrial Maze procedure seems to be as effective as the bi-atrial procedure and restores SR in 82% of patients.

Acute and long-term clinical significance of myocardial contusion following blunt thoracic trauma: results of a prospective study.

BACKGROUND: The clinical significance of myocardial contusion (MC) following blunt thoracic trauma is still unknown. Accordingly, in this prospective study in a regional trauma center we investigated the acute and long-term clinical significance of MC. METHODS: One-hundred eighteen patients with manifest or suspected blunt thoracic trauma were evaluated for cardiac injury. Initial assessment was based on results of electrocardiographic, echocardiographic, and serial enzyme measurements. A follow-up (FU) assessment conducted at 3 and 12 months, respectively, was performed using electrocardiography, echocardiography, and a bicycle ergometry exercise test. RESULTS: Of the 118 patients in the total sample, 67 (56.8%) required admission to the surgical intensive care unit (SICU) because of the severity of their noncardiac injuries. Fourteen patients of the total sample (11.8%) were diagnosed with MC and 13 of these (92.9%) belonged to the intensive care admissions, thus representing an incidence of 19.4% in this patient group. During the hospitalization period none of the patients with MC experienced acute cardiac complications. Eighty-six patients (72.0%) were assessed at FU. No new pathologies were found except in one patient. Exercise testing revealed no ECG abnormalities and none of the patients experienced limitations on the bicycle ergometer due to a cardiac cause. CONCLUSIONS: The incidence of 19.7% of MC in our patients with blunt chest injury requiring intensive care treatment indicates that this condition is frequent in polytraumatized patients. Outcome and prognosis in patients with MC is favorable and, thus, routine cardiac work-up is not indicated. Specific diagnostic and therapeutic measures should be limited to cases where cardiac complications develop.