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Paul Dorian

Publications and source records attributed to Paul Dorian.

At least 19 recordsLinked to original sources

Improving SVT discrimination in single-chamber ICDs: a new electrogram morphology-based algorithm.

INTRODUCTION: Wide-spread adoption of ICD therapy has focused efforts on improving the quality of life for patients by reducing "inappropriate" shock therapies. To this end, distinguishing supraventricular tachycardia from ventricular tachycardia remains a major challenge for ICDs. More sophisticated discrimination algorithms based on ventricular electrogram morphology have been made practicable by the increased computational ability of modern ICDs. METHODS AND RESULTS: We report results from a large prospective study (1,122 pts) of a new ventricular electrogram morphology tachycardia discrimination algorithm (Wavelet Dynamic Discrimination, Medtronic, Minneapolis, MN, USA) operating at minimal algorithm setting (RV coil-can electrogram, match threshold of 70%). This is a nonrandomized cohort study of ICD patients using the morphology discrimination of the Wavelet algorithm to distinguish SVT and VT/VF. The Wavelet criterion was required ON in all patients and all other supraventricular tachycardia discriminators were required to be OFF. Spontaneous episodes (N = 2,235) eligible for ICD therapy were adjudicated for detection algorithm performance. The generalized estimating equations method was used to remove bias introduced when an individual patient contributes multiple episodes. Inappropriate therapies for supraventricular tachycardia were reduced by 78% (90% CI: 72.8-82.9%) for episodes within the range of rates where Wavelet was programmed to discriminate. Sensitivity for sustained ventricular tachycardia was 98.6% (90% CI: 97-99.3%) without the use of high-rate time out. CONCLUSIONS: Results from this prospective study of the Wavelet electrogram morphology discrimination algorithm operating as the sole discriminator in the ON mode demonstrate that inappropriate therapy for supraventricular tachycardia in a single-chamber ICD can be dramatically reduced compared to rate detection alone.

Algorithms↗

Electrical storm in patients with an implantable defibrillator: incidence, features, and preventive therapy: insights from a randomized trial.

AIMS: The purpose of this study was to assess the incidence, features, and clinical sequelae of 'electrical storm' (ES). METHODS AND RESULTS: This study is a prospectively designed secondary analysis of SHIELD; a randomized trial of azimilide for suppression of ventricular tachycardia/fibrillation (VT/VF) leading to implanted cardioverter defibrillator (ICD) therapies. Systematic and rigorous follow-up and blinded adjudication of ICD therapy allowed identification of all ESs (>/=3 separate VT/VF episodes leading to ICD therapies within 24 h). Of 633 ICD recipients, 148 (23%) experienced at least one ES over 1-year follow-up. No clinical predictors of ES were identified. Frequent VT episodes accounted for 91% of all ESs, with the remaining being VF alone or both VT plus VF. ES led to a 3.1-fold increase in arrhythmia-related hospitalization (95% CI 2.3-4.3; P<0.0001) compared with patients with isolated VT/VF, and to a 10.2-fold increase (95% CI 6.4-16.3; P<0.0001) compared with patients without VT/VF. Compared with placebo, azimilide (75 and 125 mg/day) reduced the risk of recurrent ES by 37% (HR=0.63, 95% CI 0.35-1.11, P=0.11) and 55% (HR=0.45, 95% CI 0.23-0.87, P=0.018), respectively. However, the reduction in time-to-first ES did not reach statistical significance by both doses (75 and 125 mg) of azimilide (HR=0.82, 95% CI 0.56-1.19, P=0.29 and HR=0.69, 95% CI 0.46-1.04, P=0.07), respectively. CONCLUSION: ES is common and unpredictable in ICD recipients and it is a strong predictor of hospitalization.

Anti-Arrhythmia Agents↗

Cardiac electrophysiological consequences of neuromuscular incapacitating device discharges.

OBJECTIVES: The purpose of this study was to evaluate the cardiac consequences of neuromuscular incapacitating device (NID)/stun gun discharge in an experimental model. BACKGROUND: The large-voltage electrical discharges from NIDs have been suggested to pose a risk for triggering cardiac arrhythmias. METHODS: Intracardiac catheters and blood pressure transducers were inserted before the application of NID discharges in six anesthetized pigs. Two different commercially available models (NID-1 and NID-2), two different vectors of discharges (thoracic: parallel to the long axis of the heart on the chest wall, and nonthoracic: away from the chest, across the abdomen), and two different durations of discharge (5 and 15 s) were tested. The effect of simulated adrenergic stress using epinephrine was also evaluated. RESULTS: We studied a total of 150 discharges to 6 pigs; 74 of these discharges resulted in stimulation of the myocardium, as documented by electrical capture (mean ventricular rate during stimulation and capture, 324 +/- 66 beats/min). Of the 94 thoracic discharges, 74 stimulated the myocardium, compared with none from 56 nonthoracic discharges (p < 0.0001). During 16 discharges with epinephrine, there were 13 episodes of stimulation of the myocardium, of which 1 induced ventricular fibrillation and 1 caused ventricular tachycardia. Thoracic discharges from NID-1 were more likely to stimulate the myocardium than those from NID-2 (98% vs. 54%, p = 0.0007). CONCLUSIONS: In an experimental model, NID discharges across the chest can produce cardiac stimulation at high rates. This study suggests that NIDs may have cardiac risks that require further investigation in humans.

Animals↗

Quality of life and exercise performance in patients in sinus rhythm versus persistent atrial fibrillation: a Veterans Affairs Cooperative Studies Program Substudy.

OBJECTIVES: The purpose of this study was to determine quality of life (QOL) and exercise performance (EP) in patients with persistent atrial fibrillation (AF) converted to sinus rhythm (SR) compared with those remaining in or reverting to AF. BACKGROUND: Restoration of SR in patients with AF improving QOL and EP remains controversial. METHODS: Patients with persistent AF were randomized double-blind to amiodarone, sotalol, or placebo. Those not achieving SR at day 28 were cardioverted and classified into SR or AF groups at 8 weeks (n = 624) and 1 year (n = 556). The QOL (SF-36), symptom checklist (SCL), specific activity scale (SAS), AF severity scale (AFSS), and EP were assessed. RESULTS: Favorable changes were seen in SR patients at 8 weeks in physical functioning (p < 0.001), physical role limitations (p = 0.03), general health (p = 0.002), and vitality (p < 0.001), and at 1 year in general health (p = 0.007) and social functioning (p = 0.02). Changes in the scores for SCL severity (p = 0.01), functional capacity (p = 0.003), and AFSS symptom burden (p < 0.001) at 8 weeks and in SCL severity (p < 0.01) and AF symptom burden (p < 0.001) at 1 year showed significant improvements in SR versus AF. Symptomatic patients were more likely to have improvement. The EP in SR versus AF was greater from baseline to 8 weeks (p = 0.01) and to 1 year (p = 0.02). The EP correlated with physical functioning and functional capacity except in the AF group at 1 year. CONCLUSIONS: In patients with persistent AF, restoration and maintenance of SR was associated with improvements in QOL measures and EP. There was a strong correlation between QOL measures and EP.

Activities of Daily Living↗

Cumulative experience of azimilide-associated torsades de pointes ventricular tachycardia in the 19 clinical studies comprising the azimilide database.

OBJECTIVES: The purpose of this study was to assess the incidence, temporal characteristics, and risk factors associated with azimilide-associated torsades de pointes (TdP) ventricular tachycardia. BACKGROUND: Azimilide dihydrochloride is a class III antiarrhythmic drug possessing Ikr and Iks channel-blocking properties. METHODS: Oral azimilide (75 to 125 mg/day) was taken by 5,375 patients in 19 clinical trials conducted at 775 international centers. Of 3,964 patients in double-blind studies, 1,427 had a history of atrial fibrillation or other supraventricular arrhythmia, 510 had an implantable cardioverter-defibrillator, and 2,027 were post-myocardial infarction patients with a left ventricular ejection fraction < or =35%. RESULTS: The TdP occurred in 56 patients assigned to azimilide, was dose-related, and tended to occur earlier with an azimilide-loading regimen. Forty-three percent of TdP patients had a QT interval corrected by Bazett's formula, for heart rate, (QTc) > or =500 ms at the time of or before the TdP occurrence. Significant risk factors using logistic regression were increasing age, female gender, diuretic use, and lack of aspirin use. CONCLUSIONS: Azimilide-associated TdP has characteristics and risk factors similar to other Ikr blockers. However, there is a distinctive temporal profile. The TdP events are not concentrated in the first week. The azimilide-associated TdP rate is 1% (95% confidence interval 0.78 to 1.35) and is not increased in patients with low left ventricular ejection fraction, even in women.

Aged↗

Psychological correlates of quality of life in atrial fibrillation.

OBJECTIVE: Atrial fibrillation (AF) is associated with significant health-related quality of life (QoL) impairments. Markers of heart disease severity have explained little variance in QoL and it is unclear what other factors will better account for the observed differences in adjustment. We examined whether specific personality traits and illness management styles would help explain the severity of QoL impairments reported in this population. METHODS: Patients with AF (N = 93) completed validated questionnaires measuring disease burden (dependent variables: physical and mental QoL, symptom severity, psychological distress), personality (independent variables: anxiety sensitivity, optimism), and illness management style (mediating variable: symptom preoccupation). Hypothesized relationships were evaluated using mediation models. RESULTS: Anxiety sensitivity was associated with poorer physical and mental QoL, greater symptom severity, and higher distress. Optimism was correlated with better mental QoL and lower distress, but unrelated to physical QoL and symptom severity. Symptom preoccupation significantly mediated the relationships between anxiety sensitivity and each of the QoL measures, as well as the relationships between optimism and mental well-being. CONCLUSIONS: Personality traits and illness management styles are important to consider when assessing the impact of AF on QoL. The data support a cognitive-behavioral model that explains the direct and indirect relationships between psychological predictors and multiple indices of QoL.

Aged↗

Effect of amiodarone and sotalol on ventricular defibrillation threshold: the optimal pharmacological therapy in cardioverter defibrillator patients (OPTIC) trial.

BACKGROUND: Many patients with implanted cardioverter defibrillators (ICDs) receive adjunctive antiarrhythmic drug therapy, most commonly amiodarone or sotalol. The effects of these drugs on defibrillation energy requirements have not been previously assessed in a randomized controlled trial. METHODS AND RESULTS: The Optimal Pharmacological Therapy in Cardioverter Defibrillator Patients (OPTIC) trial was a randomized clinical trial evaluating the efficacy of amiodarone plus beta-blocker and sotalol versus beta-blocker alone for reduction of ICD shocks. Within OPTIC, a prospectively designed substudy evaluated the effects of the 3 treatment arms on defibrillation energy requirements. Defibrillation thresholds (DFTs) were measured (binary step-down protocol) at baseline and again after 8 to 12 weeks of therapy in 94 patients, of whom 29 were randomized to receive beta-blocker therapy (control group), 35 to amiodarone plus beta-blocker, and 30 to sotalol. In the control group, the mean DFT decreased from 8.77+/-5.15 J at baseline to 7.13+/-3.43 J (P=0.027); in the amiodarone group, DFT increased from 8.53+/-4.29 to 9.82+/-5.84 J (P=0.091). In the sotalol group, DFT decreased from 8.09+/-4.81 to 7.20+/-5.30 J (P=0.21). DFT changes in the beta-blocker and the amiodarone group were significantly different (P=0.006). In all patients, adequate safety margins for defibrillation were maintained. No clinical variable predicted baseline DFT or changes in DFT on therapy. CONCLUSIONS: Although amiodarone increased DFT, the effect size with modern ICD systems is very small. Therefore, DFT reassessment after the institution of antiarrhythmic drug therapy with amiodarone or sotalol is not routinely required.

Adrenergic beta-Antagonists↗

Comparison of beta-blockers, amiodarone plus beta-blockers, or sotalol for prevention of shocks from implantable cardioverter defibrillators: the OPTIC Study: a randomized trial.

CONTEXT: Implantable cardioverter defibrillator (ICD) therapy is effective but is associated with high-voltage shocks that are painful. OBJECTIVE: To determine whether amiodarone plus beta-blocker or sotalol are better than beta-blocker alone for prevention of ICD shocks. DESIGN, SETTING, AND PATIENTS: A randomized controlled trial with blinded adjudication of events of 412 patients from 39 outpatient ICD clinical centers located in Canada, Germany, United States, England, Sweden, and Austria, conducted from January 13, 2001, to September 28, 2004. Patients were eligible if they had received an ICD within 21 days for inducible or spontaneously occurring ventricular tachycardia or fibrillation. INTERVENTION: Patients were randomized to treatment for 1 year with amiodarone plus beta-blocker, sotalol alone, or beta-blocker alone. MAIN OUTCOME MEASURE: Primary outcome was ICD shock for any reason. RESULTS: Shocks occurred in 41 patients (38.5%) assigned to beta-blocker alone, 26 (24.3%) assigned to sotalol, and 12 (10.3%) assigned to amiodarone plus beta-blocker. A reduction in the risk of shock was observed with use of either amiodarone plus beta-blocker or sotalol vs beta-blocker alone (hazard ratio [HR], 0.44; 95% confidence interval [CI], 0.28-0.68; P<.001). Amiodarone plus beta-blocker significantly reduced the risk of shock compared with beta-blocker alone (HR, 0.27; 95% CI, 0.14-0.52; P<.001) and sotalol (HR, 0.43; 95% CI, 0.22-0.85; P = .02). There was a trend for sotalol to reduce shocks compared with beta-blocker alone (HR, 0.61; 95% CI, 0.37-1.01; P = .055). The rates of study drug discontinuation at 1 year were 18.2% for amiodarone, 23.5% for sotalol, and 5.3% for beta-blocker alone. Adverse pulmonary and thyroid events and symptomatic bradycardia were more common among patients randomized to amiodarone. CONCLUSIONS: Despite use of advanced ICD technology and treatment with a beta-blocker, shocks occur commonly in the first year after ICD implant. Amiodarone plus beta-blocker is effective for preventing these shocks and is more effective than sotalol but has an increased risk of drug-related adverse effects.Clinical Trials Registration ClinicalTrials.gov Identifier: NCT00257959.

Adrenergic beta-Antagonists↗

Gender differences and quality of life in atrial fibrillation: the mediating role of depression.

OBJECTIVE: This study investigated gender differences, depression, and health-related quality of life (QoL) in a cross-sectional sample of patients with atrial fibrillation (AF). METHODS: This cross-sectional study involved a convenience sample of AF patients from two tertiary-care clinics in Toronto, Canada. Ninety-three AF patients completed psychometrically validated measures of generic QoL and depression. Mediation analyses evaluated the relationship between gender and QoL using depression as mediating variable. RESULTS: Relative to male patients, female patients reported lower physical, but not mental, QoL. Gender was associated with both depression and physical QoL, while depression was correlated with poorer physical QoL. Path analyses demonstrated that depression significantly mediated the relationship between gender and physical QoL. CONCLUSION: Among AF patients, female patients report lower physical QoL relative to male patients, and this relationship may be mediated by self-reported symptoms of depression. Albeit correlational, the findings underscore the need to develop a better understanding of the role of depression in physical QoL, especially when considering the burden of AF in women.

Aged↗

Canadian Cardiovascular Society consensus conference recommendations on heart failure 2006: diagnosis and management.

Heart failure remains a common diagnosis, especially in older individuals. It continues to be associated with significant morbidity and mortality, but major advances in both diagnosis and management have occurred and will continue to improve symptoms and other outcomes in patients. The Canadian Cardiovascular Society published its first consensus conference recommendations on the diagnosis and management of heart failure in 1994, followed by two brief updates, and reconvened this consensus conference to provide a comprehensive review of current knowledge and management strategies. New clinical trial evidence and meta-analyses were critically reviewed by a multidisciplinary primary panel who developed both recommendations and practical tips, which were reviewed by a secondary panel. The resulting document is intended to provide practical advice for specialists, family physicians, nurses, pharmacists and others who are involved in the care of heart failure patients. Management of heart failure begins with an accurate diagnosis, and requires rational combination drug therapy, individualization of care for each patient (based on their symptoms, clinical presentation and disease severity), appropriate mechanical interventions including revascularization and devices, collaborative efforts among health care professionals, and education and cooperation of the patient and their immediate caregivers. The goal is to translate best evidence-based therapies into clinical practice with a measureable impact on the health of heart failure patients in Canada.

Canada↗

Universal access -- but when? Treating the right patient at the right time: access to electrophysiology services in Canada.

The Canadian Cardiovascular Society Access to Care Working Group has published a series of commentaries on access to cardiovascular care in Canada. The present article reviews the evidence for timely access to electrophysiology services. Using the best available evidence along with expert consensus by the Canadian Heart Rhythm Society, the panel proposed a series of benchmarks for access to the full scope of electrophysiology services, from initial consultation through to operative procedures. The proposed benchmarks are presented herein.

Canada↗

A novel, simple scale for assessing the symptom severity of atrial fibrillation at the bedside: the CCS-SAF scale.

BACKGROUND: The severity of symptoms caused by atrial fibrillation (AF) is extremely variable. Quantifying the effect of AF on patient well-being is important but there is no simple, commonly accepted measure of the effect of AF on quality of life (QoL). Current QoL measures are cumbersome and impractical for clinical use. OBJECTIVE: To create a simple, concise and readily usable AF severity score to facilitate treatment decisions and physician communication. METHODS: The Canadian Cardiovascular Society (CCS) Severity of Atrial Fibrillation (SAF) Scale is analogous to the CCS Angina Functional Class. The CCS-SAF score is determined using three steps: documentation of possible AF-related symptoms (palpitations, dyspnea, dizziness/syncope, chest pain, weakness/fatigue); determination of symptom-rhythm correlation; and assessment of the effect of these symptoms on patient daily function and QoL. CCS-SAF scores range from 0 (asymptomatic) to 4 (severe impact of symptoms on QoL and activities of daily living). Patients are also categorized by type of AF (paroxysmal versus persistent/permanent). The CCS-SAF Scale will be validated using accepted measures of patient-perceived severity of symptoms and impairment of QoL and will require 'field testing' to ensure its applicability and reproducibility in the clinical setting. CONCLUSIONS: This type of symptom severity scale, like the New York Heart Association Functional Class for heart failure symptoms and the CCS Functional Class for angina symptoms, trades precision and comprehensiveness for simplicity and ease of use at the bedside. A common language to quantify AF severity may help to improve patient care.

Atrial Fibrillation↗

Blockade of IKs by HMR 1556 increases the reverse rate-dependence of refractoriness prolongation by dofetilide in isolated rabbit ventricles.

1. The rate-dependent contributions of the rapid and slow components of the cardiac delayed rectifier K+ current (IKr and IKs, respectively) to repolarization are not fully understood. It is unclear whether the addition of IKs block will attenuate reverse rate-dependence seen after IKr block. 2. The individual and combined electrophysiological effects of selective IKr and IKs blockers, dofetilide and HMR 1556, respectively, were evaluated using Langendorff-perfused rabbit hearts. Monophasic action potential duration at 90% repolarization (MAPD90) and ventricular effective refractory period (VERP) were determined at cycle lengths (CLs) of 200-500 ms (at 50 ms intervals). 3. Dofetilide (1-100 nM) prolonged MAPD90 in a concentration-dependent manner (P < 0.001, n = 6) with reverse rate-dependence (P < 0.0001). In contrast, HMR 1556 (10-240 nM) alone did not prolong MAPD90. However, in the presence of 7.5 nM dofetilide, HMR 1556 (100 nM) increased the extent of reverse rate-dependence by further prolonging MAPD90 at CLs of 400, 450 and 500 ms (P < 0.05, n = 9) and, to a lesser extent, at shorter CLs (e.g. by 17 +/- 4 ms at CL 500 vs 2 +/- 3 ms at CL 200 ms). 4. Effects of dofetilide and HMR 1556 on VERP were similar to those on MAPD90. The slope of the VERP vs CL relation was steeper after the combination (0.081 +/- 0.013) than after dofetilide alone (0.028 +/- 0.018, P < 0.01, n = 9). 5. Blockade of rabbit IKs increased reverse rate-dependence of IKr block.

Action Potentials↗

Rate control in atrial fibrillation: looking beyond the average heart rate.

PURPOSE OF REVIEW: The aim of this article is to provide a perspective on rate control in atrial fibrillation which emphasizes patient wellbeing (exercise tolerance, symptoms, quality of life) over attempts to reduce resting or exercise heart rate to an arbitrary range. RECENT FINDINGS: Recent trials of rhythm versus rate control strategies of treatment in patients with atrial fibrillation suggest that rate control is a viable first line strategy in many patients. The adverse consequences of atrial fibrillation with rapid ventricular response are partly due to factors other than rate itself, such as irregularity of ventricular response, and variable changes in autonomic nervous system output. Digoxin, calcium channel blockers, and beta-blockers cause a similar reduction in resting heart rate. Beta blockers are the most potent at reducing exercise heart rate, followed by calcium channel blockers and digoxin. Exercise tolerance is occasionally improved by digoxin, sometimes improved by calcium channel blockers and not improved by (and sometimes decreased by) beta-blockers. Information about quality of life with different rate control regimens is sparse. SUMMARY: Rate control in atrial fibrillation provides important benefits to patients in terms of symptoms, quality of life and prevention of late consequences of uncontrolled rate (such as tachycardia induced cardiomyopathy). Restricting treatment objectives to achievement of a specific heart rate range on resting or exercise electrocardiogram may result in lack of patient benefit or worsened symptoms. Understanding the nuances of rate control when treating individual patients and interpreting existing evidence allows patients to experience the most benefit from this treatment strategy.

Anti-Arrhythmia Agents↗

Continuous template collection and updating for electrogram morphology discrimination in implantable cardioverter defibrillators.

INTRODUCTION: Electrogram morphology analysis improves discrimination of supraventricular tachycardias (SVTs) from ventricular tachycardias (VTs) in implantable cardioverter defibrillators (ICDs), but electrogram morphology may change with lead maturation, drugs, or disease progression. We report the clinical performance of an automatic algorithm that creates and updates templates from non-paced, slow rhythm and continuously checks the quality of the template used for arrhythmia discrimination. METHODS AND RESULTS: We studied this algorithm in 193 patients with single-chamber ICDs (Marquis VR, Medtronic Inc., Minneapolis, MN, USA). Of the 112 patients who completed 6-month follow-up, 99.1% of the patients had > or =1 automatic template created. Match scores between template and ongoing rhythm are computed using Haar Wavelets. Of the 435 automatic templates evaluated at follow-up, 423 (97.2%) had a median match score > or =70%. Intrinsic rhythm at 1 month had significantly higher match scores (P < 0.001) with automatic templates (90.3 +/- 7.0%) than with manual templates (85.7 +/- 10.9%) generated at pre-hospital discharge (PHD). The percentage of appropriately rejected SVTs was slightly higher with the automatic template (280/339 episodes) than with the manual template at PHD (272/339 episodes) while the Wavelet detection of VT was the same (218/220 episodes). CONCLUSIONS: In patients receiving ICDs, the automatic templates were successfully created during a 6-month follow-up period, and consistently matched the patients' intrinsic rhythm at the nominal match threshold. Both early (<1 month postimplant) and late (1- to 3-month follow-up period) changes in electrogram morphology were identified, confirming the need for automatic template updating.

Algorithms↗

The future of atrial fibrillation therapy.

Today management of atrial fibrillation (AF) centers on restoration and maintenance of normal sinus rhythm or control of the ventricular rate response to AF. Current guidelines state that rhythm and rate control strategies should be considered therapeutically equivalent, but recognize that no "one size fits all," an approach consistent with growing recognition of the heterogeneity of AF. As data from the Sotalol Amiodarone Atrial Fibrillation Efficacy Trial clearly demonstrate, conventional antiarrhythmics have a role in highly symptomatic AF accompanied by decreased quality of life. However, for many AF patients such drugs lack efficacy, have potentially serious side effects, and are poorly tolerated. In parallel with the development of more effective and safer antiarrhythmics, nontraditional approaches to prevention and treatment of AF are being explored. Treatments not considered "antiarrhythmic" that may prevent or forestall AF include aggressive antihypertensive therapy with angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, and some, but not all, beta-blockers and calcium channel antagonists, especially when used as adjunctive therapy. Other approaches include statins, steroids, and fish oil to reduce atrial fibrosis and inflammation, and pacemakers to prevent bradycardia-mediated AF and as a pacing preventive strategy in selected patients. Ablative techniques with potential to cure AF are gaining popularity, but are not yet simple, straightforward, and risk-free procedures. In the future, treatment of AF will progress beyond today's focus on AF as a purely electrocardiographic disease toward a patient and context-specific management strategy involving multiple treatment modalities.

Anti-Arrhythmia Agents↗

Using transthoracic two-dimensional echocardiography to guide the placement of coronary sinus catheters: a randomized study.

OBJECTIVE: To assess the value of transthoracic echocardiography (TTE) as an image guide in placing a coronary sinus catheter into the coronary sinus. METHODS: Sixty consecutive patients undergoing electrophysiologic study were randomized to TTE (30 patients, "TTE group") or x-ray fluoroscopy (30 patients, "x-ray group") as an image guide to assist in the placement of a coronary sinus catheter. RESULTS: The success rate of placing the coronary sinus catheter was 96.7% in TTE group and 100% in x-ray group (P > 0.05). The procedure duration was 5.8 +/- 5.7 minutes in TTE group and 5.9 +/- 3.3 minutes in x-ray group (P > 0.05), The x-ray exposure time was 0.15 +/- 0 minute in TTE group and 4.2 +/- 2.8 minutes in x-ray group (P < 0.0001). CONCLUSION: Using TTE as an image guide, coronary sinus cannulation is feasible and as rapid as standard x-ray fluoroscopy, without the radiation risk.

Adult↗