A User‐Friendly Method of Cardiac Venous System Visualization in 64‐Slice Computed Tomography

Background: Previsualization of the cardiac venous system is very important for some techniques, for example, cardiac resynchronization therapy (CRT). The aim of this study was to propose a new, user‐friendly method of cardiac venous system visualization in 64‐slice computed tomography (CT). Methods: In 112 patients (66 M) aged 58 ± 11 standard deviation, a 64‐slice CT with a retrospective electrocardiogram gating was performed due to a suspicion of ischemic heart disease. Special attention was paid to the requirements for image reconstruction useful for CRT. Results: In 74% of the patients, it was possible to obtain similar images to those during the CRT implantation procedure within anterior‐posterior, left anterior oblique, and right anterior oblique views. The coronary sinus was clearly visible in all cases, the ostium measured 12.9 ± 5.9 mm, and the angle of entrance 99 ± 12 degrees. In all patients it was possible to demonstrate more than one vein; in 95%, at least one vein was clearly visible in the target area. Among the target veins, the posterolateral vein was visible most frequently (78%) in the cases as well as the lateral vein (78%). Conclusion: The proposed scheme in 64‐slice computed tomography enables images to be generated similar to the intraoperative fluoroscopy, which can be useful in techniques where previsualization of the cardiac venous system is recommended.     

IMAGE BASED RENAL STONE TRACKING TO IMPROVE EFFICACY IN EXTRACORPOREAL LITHOTRIPSY

Purpose

We describe a method to reduce the number of shocks necessary to fragment renal stones during extracorporeal shock wave lithotripsy by automatically taking into account stone movements.

Materials and Methods

Echotrack computer software was developed and implemented on a lithotriptor. One software module uses image processing to detect instantaneous stone location based on ultrasound images generated by the lithotriptor. A second module uses the detected location to control the shock wave generator position, and automatically adjusts it to improve coincidence between the focal volume and stone. The reliability of the tracking algorithm was clinically tested in 65 patients with renal stones. These in vivo tests were qualitative and the goal was to assess software ability to track stones during actual treatments. A quantitative evaluation of the reduction in shocks necessary for fragmentation was performed in vitro. Artificial stones were moved according to computer generated trajectories. Each trajectory was applied once with and once without automatic adjustment of the generator position.

Results

The in vivo tests demonstrated software ability to track stones as far as they were visible in the images. During in vitro tests automatic adjustments of the generator position reduced the number of shocks necessary to fragment stones completely by a factor of 1.64.

Conclusions

Image based renal stone tracking software that automatically adjusts the shock wave generator position according to the displacement of renal stones is useful during extracorporeal shock wave lithotripsy. Treatment time was significantly shorter with this software.     

INTRAVESICAL INTERLEUKIN-2 IN T1 PAPILLARY BLADDER CARCINOMA: REGRESSION OF MARKER LESION IN 8 OF 10 PATIENTS

Purpose

We evaluate the therapeutic effect of intravesical interleukin-2 (IL-2) on T1 papillary bladder carcinoma after incomplete transurethral resection.

Materials and Methods

After incomplete transurethral resection we treated 10 patients in whom the marker lesion was left in place with 3 × 10 sup 6 Chiron units IL-2 in 50 ml. saline plus 0.1% human serum albumin. The solution remained in the bladder for 2 hours and it was instilled on 5 consecutive days. The effect of IL-2 treatment on the marker lesion was evaluated by cystoscopy and repeat biopsy of the marker site 2 months after treatment. In addition, the effect on the recurrence of bladder tumors was studied.

Results

At 2 months 8 of the 10 marker lesions (80%) had completely regressed and there were no tumor cells on repeat biopsy. Four patients remained tumor-free after 30 to 54 months. We noted no toxic effects. In 1 patient with a 7-year history of bladder cancer the marker was only partially regressed after 2 months. After removal of the marker this patient remained tumor-free at a followup of 54 months.

Conclusions

To our knowledge this report represents the first study of the effect of IL-2 on marker lesions left in place after transurethral resection. The results indicate that IL-2 instillations are feasible, and the combination of transurethral resection and IL-2 instillation may have a powerful antitumor effect. The therapeutic effects may not simply be due to intravesical IL-2, because previous transurethral resection probably caused some influx of infiltrating cells and the marker may have had tumor associated antigens. Consequently these effects may be due to the interaction of tumor associated antigens, infiltrating cells and IL-2.     

Implantable Cardioverter‐Defibrillator in Patients With Hypertrophic Cardiomyopathy: Efficacy and Complications of the Therapy in Long‐Term Follow‐up

ICD in Hypertrophic Cardiomyopathy Patients. Introduction: Although implantable cardioverter‐defibrillators (ICDs) are used in sudden cardiac death (SCD) prevention in high‐risk patients with hypertrophic cardiomyopathy (HCM), long‐term results as well as precise risk stratification are discussed in a limited number of reports. The aim of the study was to assess the incidence of ICD intervention in HCM patients with relation to clinical risk profile. Methods and Results: We studied 104 consecutive patients with HCM implanted in a single center. The mean age of study population was 35.6 (SD, 16.2) years with the average follow‐up of 4.6 (SD, 2.6) years. ICD was implanted for secondary (n = 26) and primary (n = 78) prevention of SCD. In the secondary prevention group, 14 patients (53.8%) experienced at least 1 appropriate device intervention (7.9%/year). In the primary prevention (PP) group appropriate ICD discharges occurred in 13 patients (16.7%) and intervention rate was 4.0%/year. Nonsustained VT was the only predictive risk factor (RF) for an appropriate ICD intervention in the PP (positive predictive value 22%, negative predictive value 96%). No significant difference was observed in the incidence of appropriate ICD discharges between PP patients with 1, 2, or more RF. Complications of the treatment included: inappropriate shocks (33.7%), lead dysfunction (12.5%), and infections: 4.8% of patients. Four patients died during follow‐up. Conclusion: ICD therapy is effective in SCD prevention in patients with HCM, although the complication rate is significant. Nonsustained ventricular tachycardia seems to be the most predictive RF for appropriate device discharges. Number of RF did not impact the incidence of appropriate ICD interventions. (J Cardiovasc Electrophysiol, Vol. 21, pp. 883‐889, August 2010)     

Electrical Atrial Remodeling Assessed by Monophasic Action Potential and Atrial Refractoriness in Patients with Structural Heart Disease

The present study was performed to assess the effect of induced atrial fibrillation (AF) on atrial monophasic action potentials (MAPs) and atrial refractory period (ERP) in patients with structural heart disease. An electrode MAP catheter was placed in the right atrium to continuously measure atrial potential duration (APD₉₀) in 13 patients (coronary artery disease, 10 patients; dilated cardiomyopathy, 2 patients; hypertrophic cardiomyopathy, 1 patient) without spontaneous AF episodes. AF was induced by rapid atrial stimulation (300–1500/min). If sinus rhythm returned within 10 minutes, AF was reinduced. The atrial ERP was measured during atrial pacing at a basic cycle length of 550 ms before AF induction and after its conversion. Results: The mean atrial ERP and the atrial APD₉₀ before AF was 242 ± 34 ms and 256 ± 23 ms, respectively. ERP and APD_go shortening was observed after 3 minutes of AF. After 11 ± 0.5 min (10 min 20 s-13 min 10 s) of AF, ERP and APD₉₀ reached their minimal values of 72%± 13% and 71%± 10% of baseline, respectively. ERP and APD₉₀ returned to their initial values within 10 minutes after conversion of AF. A tendency toward longer duration of consecutive AF episodes and facilitation of their induction was observed. Conclusion: The present study confirms that short episodes of AF modify the electrophysiological properties of the atria in humans. In patients with structural heart disease, induced atrial fibrillation shortens the atrial ERP as well as the atrial APD₉₀. The changes were reversible within 10 minutes after arrhythmia termination.     

New Insight into Repolarization Abnormalities in Patients with Congenital Long QT Syndrome: the Increased Transmural Dispersion of Repoiarization

There is evidence from experimental studies that the time interval from the peak to the end of T-wave reflects the transmural dispersion in repolarization (electrical gradient) between myocardial "layers" (epicardial, M-cells, endocardial). Since Congenital Long QT Syndrome (LQTS) is considered to be classical disease or repolarisation abnormalities, we performed the present study to assess the transmtiral dispersion of repolarization in LQTS patients. The study group consisted of 17 patients: 7 LQTS pts and 10 pts from the control group. In each patient the 24-hour ECG recording was performed on magnetic tape. The interval from the peak to the end of the T-wave (TpTo) was automatically measured by Holter system during every hour as a measure of transmural dispersion of repolarisation. Thereafter the mean TpTo from 24-hours was calculated. In addition the spatial QT dispersion was measured from 12 lead ECG and 3 channel Holter tape as a difference between the shortest and the longest QT interval between leads. The values were compared between groups using the Anova test.
TpTo was 79,6±9,6 ms (72–92 ms) in LQTS group and 62,4±7,5 ms (51–70) in the control group (p< 0.001). In LQTS group TpTo was significantly longer at night hours 72,5±2 when compared to day hours 87,4±8 (p<0.01). The spatial QT dispersion was significantly higher in LQTS patients when compared to control, both in 12-lead standard and Holter ECG.
Congenital long QT syndrome is associated with increase in both transmural and spatial dispersion of repolarization. The extent of prolongation of the terminal portion of QT in patients with congenital long QT syndrome is greater at night sleep hours compared to daily activity.     

Percutaneous ultrasound-guided radiofrequency ablation for kidney tumors in patients with surgical risk

OBJECTIVE: The aim of this study was to describe our experience with percutaneous ultrasound-guided radiofrequency ablation of kidney tumors. METHODS: From July 2002 to August 2005, 45 radiofrequency ablations (RFA) in 42 selected patients with kidney tumor were performed. The patients had either contraindications to surgery procedures or had a solitary kidney. The average tumor size was 37.5 mm (range, 18-59 mm) with the mean age of 68 years (range, 28-83 years). RFA were performed based on radiographic findings. Needle biopsy was made only twice. Monopolar Cool-tip Tyco or bipolar Celon Olympus radiofrequency devices were used. The procedure was performed under conscious sedation with local anesthesia. Treatment efficacy was assessed by computed tomography and by Doppler ultrasound. The absence of contrast enhancement on computed tomography was considered to be a successful treatment. RESULTS: The average follow up was 14 months (range, 3-36 months). In 42 tumors (93%), total absence of contrast enhancement was obtained after the initial RFA and in three tumors (7%) after the second ablation session. There were no complications following 41 procedures, including all ablations in small (<35 mm) renal masses. In four procedures, minor complications were observed. All patients are alive. There has been no need for chronic hemodialysis and, until now, we have not observed any local recurrences with the exception of one metastasis to an ipsilateral adrenal gland. CONCLUSIONS: RFA of kidney tumors is a promising alternative treatment which could be considered for patients who are not suitable for surgery.     

Therapy with Renin‐Angiotensin System Blockers after Pulmonary Vein Isolation in Patients with Atrial Fibrillation: Who Is a Responder?

Aims: The data on anti‐arrhythmic effect of renin‐angiotensin‐aldesteron system blockers (RASB) in patients with atrial fibrillation (AF) are controversially discussed. The goal of this analysis was to identify cohort of patients with AF and hypertension, who may have benefit from RASB therapy after pulmonary vein isolation (PVI). Methods: A total of 284 patients with AF and hypertension (paroxysmal AF [PAF]= 218, male = 185, age = 61 years, left ventricular ejection fraction = 60%, coronary artery disease = 42) considered for PVI were included. The patients with PAF were stratified according to time spent in AF (AF burden) within 3 months prior to admission (</> 500 hours). Further patients were divided into two groups: (1) low‐burden AF; (2) high‐burden AF (PAF and persistent AF). In 195 patients, RASB therapy was administered. A 7‐day continuous Holter electrocardiogram was performed after discharge, every 3 months thereafter and by symptoms. Results: Preventive effect of RASB was revealed in whole group (112 out of 195 [57%] vs 36 out of 89 [40%]; P = 0.025) and was more pronounced in patients with low‐burden AF (79 out of 112 [71%] receiving RASB vs 27 out of 55 [49%] being on other drugs; P = 0.013). However, efficiency of RASB failed in patients with high‐burden AF (33 out of 83 on RASB [40%] vs nine out of 34 on other drugs [27%]; P = 0.328). Conclusions: Our data suggest that RASB appears to protect against AF recurrences after PVI in patients with low‐burden paroxysmal AF. These results should be tested in a prospective study. (PACE 2010; 33:1101–1111)