First‐In‐Man Experience With a New 7F Vascular Closure Device (EXOSEAL™): The 7F ECLIPSE Study

Objective: This feasibility study examined safety and effectiveness of the new EXOSEAL? Vascular Closure Device (VCD) designed to promote hemostasis and early ambulation after percutaneous procedures. Background: Most VCDs currently approved by the United States FDA have been associated with significantly shorter time‐to‐hemostasis (TTH) and time‐to‐ambulation (TTA) compared to standard manual or mechanical compression, but their ease of use, patient comfort during deployment, and safety profiles are variable. Methods: Patients underwent diagnostic or interventional procedures using 7F introducer sheaths. Primary safety endpoint was the 30‐day combined rate of access‐related complications and primary effectiveness endpoints were TTH and TTA. Results: Sixty patients were enrolled prospectively (mean age 63.3 ± 11.3 year, 17% diabetics). Device and procedural success was achieved in 92% and 93%, respectively. Mean TTH and TTA was 3.2 ± 3.0 minutes and 3.0 ± 6.2 hours, respectively. No deaths or serious access‐related adverse events occurred. A ≥6 cm access‐site hematoma was the only adverse event, observed in 3 patients. Conclusions: Use of the 7F EXOSEAL? VCD was associated with short TTH and TTA, as well as low rates of procedural and 30‐day access‐related complications. (J Interven Cardiol 2012;25:518–525)     

Coronary Stenting with the Sirolimus-Eluting Stent in Clinical Practice: Final Results from the Prospective Multicenter German Cypher Stent Registry

Aims: Drug-eluting coronary stents (DES) have gained widespread use for the treatment of coronary artery disease. However, because of safety concerns and frequent "off-label" use data from "real life," registries are necessary to monitor indications and outcome of DES in daily clinical practice.
Methods and Results: We evaluated data from the German Cypher Stent Registry. A total of 10,894 patients treated with at least one sirolimus-eluting stent (SES) at 152 hospitals were included. Follow-up at a median of 6.4 months was available in 10,006 patients (92%). Median age was 64.8 years and 75.5% were male. Per lesion a mean of 1.09 ± 0.41 SES were implanted with a mean length of 21.1 ± 11.5mm. During follow-up, death rate was 1.8% and the rates of myocardial infarction or stroke were 2.1% and 0.5%. Any target vessel revascularization (TVR) was performed in 8.0% of patients. Independent predictors for death, myocardial infarction, or stroke were: cardiogenic shock, acute coronary syndromes, reduced left ventricular function, renal insufficiency, diabetes mellitus, advanced age, three-vessel disease, degree of stenosis, and prior myocardial infarction. Predictors for a TVR were: two- or three-vessel disease, target vessel = coronary bypass, advanced age, stent diameter, ostial lesions, indication in-stent restenosis, renal failure, and target vessel = left anterior descended artery.
Conclusions: These results demonstrate that SES use in clinical practice is safe and effective. The main predictors of clinical events during follow-up are clinical parameters whereas as predictors of TVR mainly are angiographic parameters. (J Interven Cardiol 2010;23:18–25)     

The Paclitaxel‐Eluting Coroflex™ Stent Study II (PECOPS II) Acute and 6‐Month Clinical and Angiographic Follow‐Up, 1‐Year Clinical Follow‐Up

Background and Objectives: Paclitaxel‐coated stents have proven their efficacy for reducing restenosis in de novo coronary artery lesions and in‐stent restenoses with superiority compared to bare metal stents. This study was performed to evaluate the procedural and 1 year results of the Paclitaxel‐eluting Coroflex? Please stent in coronary artery lesions. Methods: One‐hundred and twenty‐nine patients (66.2 ± 8.2 years, 31.0% diabetics, 20.2% unstable angina, 41.8% multivessel disease) were enrolled per protocol for elective single stent deployment into native de novo or post‐PTCA restenotic coronary lesions.The mean reference diameter was 2.84 ± 0.43 mm, the lesion length 12.51 ± 4.6 mm, and the minimal lumen diameter 0.75 ± 0.29 mm. Follow‐up was performed clinically in 129/129 (100%) after 6 and 12 months and angiographically in 120/129 (93%) patients after 6 months. Results: The success rates of the procedure and deployment were 100% and 95.3%, respectively. The in‐stent late loss and the late‐loss index were 0.27 ± 0.59 mm and 0.17 ± 0.40 resulting in binary in‐stent restenoses in 16/120 (13.3%) subjects and in‐segment restenoses in 20/120 (16.7%) subjects. Major adverse cardiac events occurred in 23/129 (17.8%) during the first 6 months of follow‐up with 3/129 (2.3%) myocardial infarctions, 1/129 (0.8%) secondary to stent thrombosis. From 6 to 12 months, 2/129 (1.6%) nonlesion related PCI were performed. Conclusion: The data of the Paclitaxel‐eluting Coroflex? Please stent evaluated in PECOPS II are within the range of the other currently available Paclitaxel‐eluting stent. (J Interven Cardiol 2010;23:160‐166)     

Measurement of Right Ventricular Blood Temperature During Exercise as a Means of Rate Control in Physiological Pacemakers

Several biological parameters have been suggested for rate control in physiological pacemakers in the past. Up to now, measurements of central venous blood temperature have been mostly done on dogs. We studied central venous blood temperature and heart rate in 14 healthy volunteers under conditions of treadmill and bicycle exercise with different workloads. A custom made 5F lead with a thermistor incorporated near the tip was placed at the right ventricle under fluoroscopic control. Temperature was recorded with an accuracy of 1/100°C on a digital memory device at a sampling rate of 5–10 s. We found the increase in blood temperature to be not only a function of absolute workloads but also a function of the individual's maximum exercise tolerance. Independent of the absolute increase in heart rate and temperature at a given workload, the individual's relation of increase in temperature and heart rate was found to be highly correlating (r = 0.9095). At a load of 100 W, we found a mean increase in heart rate of 52 beats and of temperature of 0.57°C, at 750 W of 74 beats/min and 0.84°C. During, as well as after, the exercise, heart rate and temperature have a parallel course. According to our data, control of physiological pacemakers by means of central venous blood temperature is possible.     

What Is the Most Appropriate Stimulation Mode in Patients with Sinus Node Dysfunction?

Sinus node disease (SND) has caused many controversies about the appropriate stimulation mode. We compared the advantages and disadvantages of VVI, AAI, DDD, and DDI mode. In an additional study, left ventricular function at rest [R] and during exercise [E] was investigated in dual chamber and ventricular stimulation mode with a stimulation rate of 70 ppm [R] and 110 ppm [E]. A total of 223 patients [pts] was investigated (67 AAI, 87 VVI, 69 DDI]. Hemodynamic disadvantages in VVI mode resulted in a 55% actuarial incidence of atrial fibrillation after five years. In AAI mode, we found another 25% complication rate due to impaired AV conduction [n = 9] or a bradyarrhythmia [n = 6] with slow ventricular response. DDD mode implies the possibility of sustaining a pacemaker mediated tachycardia. Single ventricular stimulation with a high stimulation rate (110 ppm] under E showed a worse left ventricular performance as compared to dual chamber stimulation. DDI mode shows none of the aforementioned disadvantages. To sum it up: Until a dual chamber rate responsive pacemaker becomes available, the DDI mode represents the best stimulation mode for patients with a SND.     

A Technical Approach to Optimized Atrial Recognition in the ICD:

Present-day ICD systems offer the possibility to reconstruct an intrathoracic 6-lead ECG (IT-ECG), using the defibrillator coils in the right ventricle and superior vena cava and the left-laterally positioned ICD as electrodes according to Einthoven and Goldberger. The aim of this study was to assess the feasibility of (1) automated P wave recognition in the IT-ECG without an additional atrial electrode as the basis of AV synchronous ventricular pacing (VDD) and for improved differentiation between supraventricular tachyarrhythmias and, (2) the automated detection of pacing evoked atrial potentials (EAP) in dual chamber ICDs as the basis for atrial "autocapture " pacing systems. In 27 patients during ICD implanation intraoperatively, the IT-ECG was digitally recorded. A recently established algorithm for automatic P wave and EAP detection correctly identified 1,663/1,672 (99.5%) P waves (oversensing rate 0.6%) and 543/554 (98.0%) EAP (no oversensing). During subthreshold atrial stimulation, 405/412 (98.3%) P waves were correctly identified (oversensing due to pacemaker spikes,   n = 421   , without subsequent EAP, 1.9%,   n = 8   ). During stimulated ventricular tachycardia in 26/27 patients retrograde P wave or AV dissociation were identified. The 6-lead IT-ECG, easily implementable in ICD systems, is a diagnostic tool providing reliable information about atrial activation, serving as a basis for VDD pacing in single chamber ICD systems, allowing reliable EAP recognition that enables atrial "autocapture " pacing in dual chamber ICDs, and improves the differentiation between supraventricular and ventricular tachycardia. (PACE 2003; 26[Pt. I]:1472–1478)     

Influence of Polarity Reversal on de-fibrillation Success with Biphasic Shocks and a Transvenous/Subcutaneous Defibrillator System in a Porcine Animal Model

Clinical studies show that polarity reversal affects de-fibrillation success in transvenous monophasic defibrillators. Current devices use biphasic shocks for de-fibrillation. We investigated in a porcine animal model whether polarity reversal influences de-fibrillation success with biphasic shocks. In nine anesthetized, ventilated pigs, the de-fibrillation efficacy of biphasic shocks (14.3 ms and 10.8 ms pulse duration) with “initial polarity” (IP, distal electrode = cathode) and “reversed polarity” (RP, distal electrode = anode) delivered via a transvenous/subcutaneous lead system was compared. Voltage and current of each defibrillating pulse were recorded on an oscilloscope and impedance calculated as voltage divided by current. Cumulative de-fibrillation success was significantly higher for RP than for IP for both pulse durations (55% vs 44%, P = 0.019) for 14.3 ms (57% vs 45%, P < 0.05) and insignificantly higher for 10.8 ms (52% vs 42%, P = n.s.). Impedance was significantly lower with RP at the trailing edge of pulse 1 (IP: 44 ± 8.4 vs RP: 37 ± 9.3 with 14.3 ms, P < 0.001 and IP: 44 ± 6.2 vs RP: 41 ± 7.6 Ω with 10.8 ms, P < 0.001) and the leading edge of pulse 2 (IP: 37 ± 5 vs RP: 35 ± 4.2 Ω with 14.3 ms, P = 0.05 and IP: 37.5 ± 3.7 vs RP: 36 ± 5 Ω with 10.8 ms, P = 0.02). In conclusion, in this animal model, internal de-fibrillation using the distal coil as anode results in higher de-fibrillation efficacy than using the distal coil as cathode. Calculated impedances show different courses throughout the shock pulses suggesting differences in current flow during the shock.     

Sinus Node Dysfunction After Orthotopic Heart Transplantation: The Vienna Experience 1987–1993

In the present study, the annual incidence of postoperative sinus node dysfunction and the type of sinus node abnormality after cardiac transplantation were followed over a 6½-year period in 185 patients. Each year the sinus node function was systematically characterized by rhythm and corrected sinus node recovery time in a significant number of patients. Over the entire study period, there were 131 patients with normal sinus node function (corrected sinus node recovery time 318 ± 55 msec) while 54 patients had latent (n = 24, sinus rhythm, corrected sinus node recovery time 8,053 ± 2,198 msec) or manifest (n = 30, absence of sinus rhythm or pacemaker dependence) sinus node dysfunction. Twenty-nine patients had pacemaker placement. The incidence of sinus node dysfunction declined in absolute terms and when indexed by the actual number of patients transplanted per year (index 1987: 38.5; 1998: 17.6; 1989: 23.2; 1990: 29.1; 1991: 10.4; 1992: 7.5; 1993: 2.2). Among those with sinus node dysfunction, the annual percentage of patients presenting with prolonged recovery time, escape rhythm, and those reverting back to sinus rhythm until discharge did not change significantly over the study period (P = 0.22). On multivariate analysis, only the date of transplantation was significantly associated with the occurrence of postoperative sinus node deficiency (P = 0.0007) while age of recipient (P = 0.85) or donor (P = 0.96), the type of cardioplegia used (P = 0.09) and ischemic time (P = 0.09) were insignificant. This decline in the annual incidence of sinus node dysfunction most probably may be interpreted in terms of improvements in management (learning curve). It is unclear which changes in particular are responsible for this development. In view of the lack of other significant associations, this might be an indication that operative trauma plays a role in the etiology of sinus node dysfunction after cardiac transplantation.