Long-term outcomes with biodegradable polymer sirolimus-eluting stents versus durable polymer everolimus-eluting stents in ST-segment elevation myocardial infarction: 5-year follow-up of the BIOSTEMI randomised superiority trial

BACKGROUND

Biodegradable polymer sirolimus-eluting stents improve early stent-related clinical outcomes compared to durable polymer everolimus-eluting stents in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention. The long-term advantages of biodegradable polymer sirolimus-eluting stents after complete degradation of its polymer coating in patients with STEMI remains however uncertain.

METHODS

BIOSTEMI Extended Survival (BIOSTEMI ES) was an investigator-initiated, follow-up extension study of the BIOSTEMI prospective, multicentre, single-blind, randomised superiority trial that compared biodegradable polymer sirolimus-eluting stents with durable polymer everolimus-eluting stents in patients with STEMI undergoing primary percutaneous coronary intervention at ten hospitals in Switzerland. All individuals who had provided written informed consent for participation in the BIOSTEMI trial were eligible for this follow-up study. The primary endpoint was target lesion failure, defined as a composite of cardiac death, target vessel myocardial re-infarction, or clinically indicated target lesion revascularisation, at 5 years. Superiority of biodegradable polymer sirolimus-eluting stents over durable polymer everolimus-eluting stents was declared if the Bayesian posterior probability for a rate ratio (RR) of less than 1 was greater than 0·975. Analyses were performed according to the intention-to-treat principle. The study was registered with ClinicalTrials.gov, NCT05484310.

FINDINGS

Between April 26, 2016, and March 9, 2018, 1300 patients with STEMI (1622 lesions) were randomly allocated in a 1:1 ratio to treatment with biodegradable polymer sirolimus-eluting stents (649 patients, 816 lesions) or durable polymer everolimus-eluting stents (651 patients, 806 lesions). At 5 years, the primary composite endpoint of target lesion failure occurred in 50 (8%) patients treated with biodegradable polymer sirolimus-eluting stents and in 72 (11%) patients treated with durable polymer everolimus-eluting stents (difference of -3%; RR 0·70, 95% Bayesian credible interval 0·51-0·95; Bayesian posterior probability for superiority 0·988).

INTERPRETATION

In patients undergoing primary percutaneous coronary intervention for STEMI, biodegradable polymer sirolimus-eluting stents were superior to durable polymer everolimus-eluting stents with respect to target lesion failure at 5 years of follow-up. The difference was driven by a numerically lower risk for ischaemia-driven target lesion revascularisation.

FUNDING

Biotronik.

High incidence of inappropriate alarms in patients with wearable cardioverter-defibrillators: findings from the swiss WCD registry

Introduction

The wearable cardioverter defibrillator (WCD) uses surface electrodes built into the vest to detect underlying arrhythmia before initiating a treatment sequence. However, it is also prone to inappropriate detection due to artefacts.

Purpose

The aim of this study was to assess the alarm burden in patients and its possible impact on clinical outcomes.

Methods

The Swiss WCD Registry is a nationwide, retrospective, observational registry. Patients were included from December 2011 until February 2018. Clinical characteristics and data from the WCDs, including alarm burden were analysed. Recordings ≥30 seconds of length were analysed and categorized as VT/VF, atrial fibrillation (AF), supraventricular tachycardia or artefact.

Results

A total of 10'653 device alarms were documented in 324 of 456 patients (71.1%) over a mean WCD wear-time of 2.0±1.6 months. Among these, the episode duration was 30 seconds or more in 2996 (28.2%). One hundred and eleven (3.7%) were VT/VF episodes. The remaining recordings were inappropriate arrhythmia detections (2736 (91%) due to artefacts; 117 (3.7%) AF; 48 (1.6%) supraventricular tachycardia). Two-hundred and seven patients (45.0%) had 3 or more alarms per month, whereas 49 patients (10.7%) had 1 or more alarms per day. Body mass index (BMI) was significantly higher in patients with 3 or more alarms per month (p=0.002, 25.6 vs. 27.3 kg/m2) High alarm burden was not associated with a lower average daily wear time (20.8 hours vs 20.7 hours, p=0.785) or a decreased implantable cardioverter defibrillator implantation rate after stopping WCD use (48% vs 47.3%, p=0.156).

Conclusions

In patients using WCDs, alarms emitted by the device and impending inappropriate shocks were frequent and most commonly caused by artefacts. A high alarm burden did not lead to a decreased adherence, as determined by average daily wear-times. Obesity was significantly associated with a higher alarm burden.

Funding Acknowledgement

Type of funding sources: None.

Impact of contact force sensing technology on outcome of catheter ablation of idiopathic pre-mature ventricular contractions originating from the outflow tracts

AIMS

Catheter ablation of frequent idiopathic pre-mature ventricular contractions (PVC) is increasingly performed. While potential benefits of contact force (CF)-sensing technology for atrial fibrillation ablation have been assessed in several studies, the impact of CF-sensing on ventricular arrhythmia ablation remains unknown. This study aimed to compare outcomes of idiopathic outflow tract PVC ablation when using standard ablation catheters as opposed to CF-sensing catheters.

METHODS AND RESULTS

In a retrospective multi-centre study, unselected patients undergoing catheter ablation of idiopathic outflow tract PVCs between 2013 and 2016 were enrolled. All procedures were performed using irrigated-tip ablation catheters and a 3D electro-anatomical mapping system. Sustained ablation success was defined as a  ≥80% reduction of pre-procedural PVC burden determined by 24 h Holter ECG during follow-up. Overall, 218 patients were enrolled (median age 52 years, 51% males). Baseline and procedural data were similar in the standard ablation (24%) and the CF-sensing group (76%). Overall, the median PVC burden decreased from 21% (IQR 10-30%) before ablation to 0.2% (IQR 0-3.0%) after a median follow-up of 2.3 months (IQR 1.4-3.9 months). The rates of both acute (91% vs. 91%, P = 0.94) and sustained success (79% vs. 74%, P = 0.44) were similar in the standard ablation and the CF-sensing groups. No differences were observed in subgroups according to arrhythmia origin from the RVOT (65%) or LVOT (35%). Complications were rare (1.8%) and evenly distributed between the two groups.

CONCLUSION

The use of CF-sensing technology is not associated with increased success rate nor decreased complication rate in idiopathic outflow tract PVC ablation.

Early Rhythm Control Therapy in Patients with Atrial Fibrillation and Heart Failure

Supplemental Digital Content is available in the text.

Even on optimal therapy, many patients with heart failure and atrial fibrillation experience cardiovascular complications. Additional treatments are needed to reduce these events, especially in patients with heart failure and preserved left ventricular ejection fraction.

Cabins, castles, and constant hearts: rhythm control therapy in patients with atrial fibrillation

Recent innovations have the potential to improve rhythm control therapy in patients with atrial fibrillation (AF). Controlled trials provide new evidence on the effectiveness and safety of rhythm control therapy, particularly in patients with AF and heart failure. This review summarizes evidence supporting the use of rhythm control therapy in patients with AF for different outcomes, discusses implications for indications, and highlights remaining clinical gaps in evidence. Rhythm control therapy improves symptoms and quality of life in patients with symptomatic AF and can be safely delivered in elderly patients with comorbidities (mean age 70 years, 3–7% complications at 1 year). Atrial fibrillation ablation maintains sinus rhythm more effectively than antiarrhythmic drug therapy, but recurrent AF remains common, highlighting the need for better patient selection (precision medicine). Antiarrhythmic drugs remain effective after AF ablation, underpinning the synergistic mechanisms of action of AF ablation and antiarrhythmic drugs. Atrial fibrillation ablation appears to improve left ventricular function in a subset of patients with AF and heart failure. Data on the prognostic effect of rhythm control therapy are heterogeneous without a clear signal for either benefit or harm. Rhythm control therapy has acceptable safety and improves quality of life in patients with symptomatic AF, including in elderly populations with stroke risk factors. There is a clinical need to better stratify patients for rhythm control therapy. Further studies are needed to determine whether rhythm control therapy, and particularly AF ablation, improves left ventricular function and reduces AF-related complications.

Use of the wearable cardioverter-defibrillator - the Swiss experience

INTRODUCTION

Sudden cardiac death caused by malignant arrhythmia can be prevented by the use of defibrillators. Although the wearable cardioverter defibrillator (WCD) can prevent such an event, its role in clinical practice is ill defined. We investigated the use of the WCD in Switzerland with emphasis on prescription rate, therapy adherence and treatment rate.

MATERIALS AND METHODS

The Swiss WCD Registry is a retrospective observational registry including patients using a WCD. Patients were included from the first WCD use in Switzerland until February 2018. Baseline characteristics and data on WCD usage were examined for the total study population, and separately for each hospital.

RESULTS

From 1 December 2011 to 18 February 2018, a total of 456 patients (67.1% of all WCDs prescribed in Switzerland and 81.1% of all prescribed in the participating hospitals) were included in the registry. Up to 2017 there was a yearly increase in the number of prescribed WCDs to a maximum of 271 prescriptions per year. The mean age of patients was 57 years (± 14), 81 (17.8%) were female and mean left ventricular ejection fraction (EF) was 32% (± 13). The most common indications for WCD use were new-onset ischaemic cardiomyopathy (ICM) with EF ≤35% (206 patients, 45.2%), new-onset nonischaemic cardiomyopathy (NICM) with EF ≤35% (115 patients, 25.2%), unknown arrhythmic risk (83 patients, 18.2%), bridging to implantable cardioverter-defibrillator implantation or heart transplant (37 patients, 8.1%) and congenital/inherited heart disease (15 patients, 3.3%). Median wear duration was 58 days (interquartile range [IQR] 31–94) with a median average daily wear time of 22.6 hours (IQR 20–23.2). Seventeen appropriate therapies from the WCD were delivered in the whole population (treatment rate: 3.7%) to a total of 12 patients (2.6% of all patients). The most common underlying heart disease in patients with a treatment was ICM (13/17, 76.5%). There were no inappropriate treatments.

CONCLUSION

The use of WCDs has increased in Switzerland over the years for a variety of indications. There is high therapy adherence to the WCD, and a treatment rate comparable to previously published registry data. &nbsp.

911Which patients are most likely to benefit from the wearable cardioverter-defibrillator? Findings from the Swiss WCD registry

OnBehalf

Swiss WCD Registry

Introduction

 The wearable cardioverter-defibrillator (WCD) has established itself as a temporary protection from sudden arrhythmogenic death in selected patients at risk. However, it is still of debate which patients and for what duration benefit from its use. Therefore, appropriate patient selection is key. Purpose: This study reports the results of the Swiss WCD registry with an emphasis on implantable cardioverter-defibrillator (ICD) implantation rate and ICD therapies.

Methods

 We retrospectively reviewed the indications, baseline characteristics and administered therapies in patients prescribed a WCD at 12 participating centers rom 2014 until 2018 in Switzerland. Further data on medical therapy, WCD therapy adherence, and ICD implantation rates were collected. 

Results

 456 patients were included in our study comprising of 66% of all Swiss patients prescribed a WCD in the examined time period. The mean age was 57 ±14 years, 18% were female and the mean ejection fraction (EF) was 32% ± 13. Indications for WCD use and appropriate shock rate are shown in the figure. Patients wore the WCD over a median of 58 days (range 1-455) with a median daily average wear-time of 22.6 hours (range 0.6-23.8). 17 appropriate therapies were administered by the WCD to a total of 12 patients leading to a therapy rate of 2.6% over a median wear-time of 16 days (range 2-79) and to a therapy rate of 3.9% in patients with ischemic cardiomyopathy (ICM) with an EF ≤35%. ICM with an EF ≤35% and bridging to ICD-implantation or heart transplantation as indication for WCD prescription were significantly associated with an appropriate therapy (p = 0.046 and 0.003, respectively). One patient with non-ischemic cardiomyopathy (NICM) received an appropriate therapy (0.8%). The mean EF in patients receiving an appropriate therapy by the WCD was also significantly lower (p = 0.04). No patient with wearing the WCD for congenital/inherited heart disease or risk stratification with an EF >35% had a therapy administered by the WCD. There were no inappropriate therapies during the investigated time period. After cessation of WCD use EF improved to 38% ±13; ultimately, 212 patients (46%) were implanted with an ICD. During a follow-up of 476 days (range 7-2347) 22 (9.8%) patients received an appropriate therapy by their ICD. Four of the 22 had prior appropriate therapy by the WCD.

Conclusions

 ICM with severely reduced EF was the most common indication for WCD use leading to a high rate of appropriate therapy by the WCD. This, however, did not translate in a higher rate of appropriate ICD-therapies during follow-up in this subpopulation possibly due to significant improvements in their ejection fractions. Patients with NICM or congenital/inherited heart disease seldom had an appropriate therapy by the WCD.

Abstract Figure. Indications for WCD use and therapy rate

"Real world" experience in Cardiac Resynchronization Therapy at a Swiss Tertiary Care Center

BACKGROUND

Based on a reduction in morbidity and mortality, cardiac resynchronisation therapy (CRT) has evolved as a standard therapy for patients with advanced heart failure.

OBJECTIVE

To provide insight into patient demographics, safety, echocardiographic remodelling and long-term follow-up of patients treated with CRT in a "real-world" setting at a Swiss tertiary care centre.

METHODS

Patients implanted with a CRT device at the University Heart Centre Zurich between 2000 and 2015 were consecutively enrolled. Initial clinical and echocardiographic therapy response as well as long-term follow-up for mortality (defined as all-cause death, heart transplantation or ventricular assist device implantation) and hospitalisation for heart failure were assessed.

RESULTS

A total of 418 patients with a median age of 66 years at the time of CRT implantation (78% male) were enrolled. Serious peri-interventional complications (from the time of implantation up to 14 days thereafter) were rare and included systemic infections in 2.4%, pneumothorax in 3.3% and haematoma requiring revision in 2.2% of cases. Overall, the Kaplan-Meier estimate for 5-year freedom from the composite endpoint (hospitalisation for heart failure or mortality) was 55.8%; the Kaplan-Meier estimate for 5-year freedom from mortality was 64.1%. CRT was associated with a significant symptomatic improvement and left ventricular reverse remodelling. Overall, 3.9% of patients did not respond to cardiac resynchronisation therapy (decline in left ventricular ejection fraction [LVEF] >5%), whereas 35.1% experienced neither a continued decline nor a relevant improvement of LVEF (±5%). In the remaining 61% of patients we observed an improvement in LVEF of more than 5%. Forty percent and 31% of patients were super responders, defined as an absolute LVEF improvement of 10% and by a relative reduction of left ventricular end-diastolic volume index by 20% or more. Super-response to CRT was associated with a significant benefit in terms of survival and rehospitalisation rates.

CONCLUSION

Our data are consistent with large multicentre trials and indicate that CRT is similarly effective in a real-world setting in Switzerland.

Successful Cryoablation of an Anteroseptal Accessory Pathway Guided by Electroanatomical Activation Mapping

The use of electroanatomical mapping can facilitate the identification of the ideal cryoablation site by providing a three-dimensional map of the earliest activation site. Combined use of the cryoablation technology with electroanatomical mapping can further increase the precision and safety of the procedure by applying test applications at a lower energy level.

Comparison of benefit and mortality of implantable cardioverter-defibrillator therapy in patients aged ≥75 years versus those <75 years

Implantable cardioverter-defibrillator (ICD) therapy decreases arrhythmic and all-cause mortality in patients at high risk of sudden death. However, its clinical benefit in elderly patients is uncertain. The aim of this study was to assess the long-term efficacy of ICD treatment in elderly patients and to identify markers of successful ICD therapy and risk factors of mortality. We performed multivariate analysis of a prospective long-term database from 2 tertiary care centers including 936 consecutive patients with an ICD. Predictors of ICD therapy and risk factors for mortality were assessed in patients ≥75 years old at ICD implantation compared to younger patients. Mean follow-up time was 43 ± 40 months. Rates of ICD therapy were similar in the 2 age groups. No significant predictors of ICD therapy could be identified in older patients. Median estimated survival was 132 months in patients <75 years and 81 months in those ≥75 years old (p = 0.006). Decreased ejection fraction (hazard ratio 1.62 per 10% decrease, p = 0.03) and impaired renal function (hazard ratio 1.57 per 10 ml/kg/m(2) decrease in estimated glomerular filtration rate, p = 0.02) were independent risk factors of mortality in patients ≥75 years old. However, mortality of older patients was similar to that of the age-matched general population irrespective of delivery of ICD therapy. In conclusion, ICD therapy is effective for treatment of life-threatening arrhythmias in all age groups. However, prevention of sudden cardiac death may have limited impact on overall mortality in older patients. Despite a similar rate of appropriate ICD therapies, risk of death is increased 1.6-fold in ICD recipients ≥75 years old compared to younger patients. Patients with decreased ejection fraction and impaired renal function are at highest risk.

Comprehensive risk reduction in patients with atrial fibrillation: emerging diagnostic and therapeutic options--a report from the 3rd Atrial Fibrillation Competence NETwork/European Heart Rhythm Association consensus conference

While management of atrial fibrillation (AF) patients is improved by guideline-conform application of anticoagulant therapy, rate control, rhythm control, and therapy of accompanying heart disease, the morbidity and mortality associated with AF remain unacceptably high. This paper describes the proceedings of the 3rd Atrial Fibrillation NETwork (AFNET)/European Heart Rhythm Association (EHRA) consensus conference that convened over 60 scientists and representatives from industry to jointly discuss emerging therapeutic and diagnostic improvements to achieve better management of AF patients. The paper covers four chapters: (i) risk factors and risk markers for AF; (ii) pathophysiological classification of AF; (iii) relevance of monitored AF duration for AF-related outcomes; and (iv) perspectives and needs for implementing better antithrombotic therapy. Relevant published literature for each section is covered, and suggestions for the improvement of management in each area are put forward. Combined, the propositions formulate a perspective to implement comprehensive management in AF.

Long-term follow-up of patients with isolated left ventricular noncompaction: role of electrocardiography in predicting poor outcome

BACKGROUND

Abnormal baseline electrocardiograms (ECGs) are common in patients with isolated left ventricular noncompaction (IVNC). Whether certain electrocardiographic parameters are associated with a poor clinical outcome, however, remains elusive. The present study was therefore designed to comprehensively assess the predictive value of baseline ECG findings in patients newly diagnosed with IVNC.

METHODS AND RESULTS

74 patients diagnosed with IVNC were included in the analysis. During follow-up, 8 patients (11%) died of a cardiovascular cause or underwent heart transplantation (primary outcome measure). On univariate analysis, several variables, including repolarization abnormalities (ST segment elevation/depression, T-wave inversion) in the inferior leads (5-year estimator: 67.1 ± 10.7% vs. 98 ± 2.2%; P = 0.001), an increase in PQ- (hazard ratio (HR) 1.032, P=0.004) and QTc-duration (HR 1.037, P=0.001), were predictive of cardiovascular death or heart transplantation. On multivariate analysis, only PQ- and QTc-duration and the presence of repolarization abnormalities in the inferior leads remained significantly predictive of a poor outcome.

CONCLUSIONS

PQ duration, QTc duration, and repolarization abnormalities in the inferior leads are independently predictive of a poor prognosis in IVNC. Further prospective studies are required to conclusively investigate the usefulness of baseline ECG parameters for risk stratification in patients with IVNC.

Magnesium sulphate during transradial cardiac catheterization: a new use for an old drug?

OBJECTIVE

To assess the effect of intra-arterial magnesium on the radial artery during transradial cardiac catheterization.

BACKGROUND

Transradial coronary angiography has become popular in the last decade and offers several advantages over transfemoral angiography. Radial artery spasm is a major limitation of this approach, and a vasodilatory cocktail is usually given. The aim of this study was to examine the effect of magnesium sulphate on the radial artery during cardiac catheterization.

METHODS

This was a prospective, double-blind, randomized trial of 86 patients undergoing radial catheterization. Patients were randomized to receive magnesium sulphate (150 mg) or verapamil (1 mg) into the radial sheath. Radial dimensions were assessed using Doppler ultrasound. The primary endpoint of the study was a change in radial artery diameter following administration. Secondary endpoints included operator-defined radial artery spasm and patient pain.

RESULTS

Following administration of the study drug, there was an increase in radial artery diameter in both groups (p < 0.01), although the increase seen was greater in the group receiving magnesium (magnesium 0.36 +/- 0.03 mm; verapamil 0.27 +/- 0.03 mm; p < 0.05). Administration of verapamil resulted in a fall in mean arterial pressure (MAP) (change in MAP -6.6 +/- 1.4 mmHg; p < 0.01), whereas magnesium did not have a hemodynamic effect. Severe arm pain (pain score > 5) was observed in 14 (30%) patients receiving verapamil and 9 (27%) receiving magnesium (p = NS).

CONCLUSION

This study demonstrates that magnesium is a more effective vasodilator when compared to verapamil, with a reduced hemodynamic effect, and is equally effective at preventing radial artery spasm. As such, the use of this agent offers distinct advantages over verapamil during radial catheterization.

Sublingual administration of furosemide: new application of an old drug

BACKGROUND

In patients with decompensated heart failure, absorption of orally administered furosemide may be delayed, possibly leading to impaired pharmacodynamic effects. Sublingual administration may represent an alternative in such situations.

METHODS

In a crossover study including 11 healthy men, 20 mg furosemide was administered intravenously, orally and sublingually on three different days. Pharmacokinetics and pharmacodynamics were assessed from repeated blood and urine samples.

RESULTS

Compared with oral administration, sublingual administration was associated with 43% higher C(max)[difference 215 ng ml(-1), 95% confidence interval (CI) 37, 392], a higher urinary recovery (8.9 vs. 7.3 mg, difference 1.6 mg, 95% CI 0.3, 2.9), an 28% higher AUC (difference 328 ng h(-1) ml(-1), 95% CI 24, 632) and a higher bioavailability of furosemide (59 vs. 47%, difference 12.0%, 95% CI -1.2, 25.2). Sodium excretion was higher after sublingual compared with oral administration (peak excretion rate 1.8 vs. 1.4 mmol min(-1), P < 0.05), whereas urine volume did not differ significantly between the two application modes. In comparison, intravenous administration showed the expected more rapid and intense response.

CONCLUSION

Sublingually administered furosemide tablets differ in certain kinetic and dynamic properties from identical tablets given orally. Sublingual administration of furosemide may offer therapeutic advantages in certain groups of patients.

High-Density Mapping of Spontaneous Pulmonary Vein Activity Initiating Atrial Fibrillation in Humans

INTRODUCTION

High-density three-dimensional (3D) mapping of the pulmonary vein (PV)-left atrial (LA) junction was performed to characterize spontaneous PV activity in humans.

METHODS AND RESULTS

The activation patterns of ectopic beats and of the initial 2 seconds of atrial fibrillation (AF) from the PVs were analyzed using a 64-poles basket catheter. A focal mechanism was defined as a discrete site of early and centrifugal activation. Continuous activity was considered as an activation covering > or = 80% of the tachycardia beat-to-beat cycle length within the mapping field. In 35 patients, 123 spontaneous focal ectopic beats that did not induce AF and 95 that did induce AF were mapped. The mean coupling interval of ectopic discharges not inducing AF was 281 +/- 70 msec versus 236 +/- 90 msec for ectopies initiating AF (P < or = 0.01). The first ectopic activity of all 218 arrhythmogenic events showed exclusively a focal mechanism. During the 95 episodes of AF initiation, one or two ectopic beats from the PVs initiated AF in the LA in 39%, a stable focal tachycardia was recorded in 14%, continuous activity with important changes in cycle length (35 +/- 15 msec) suggestive of decremental or fibrillatory conduction was found in 18%, and in 29% the activation pattern could not be classified. No stable and sustained reentrant circuit could be identified by our mapping tool in the PV-LA junction.

CONCLUSIONS

Arrhythmogenic activity from PVs in humans is predominantly due to discrete focal activity.

Determination of furosemide in plasma and urine using monolithic silica rod liquid chromatography

In the present study we developed a fast and reliable HPLC assay for the determination of the loop diuretic furosemide in plasma and urine, using a Chromolith RP 18e (100 mm x 4.6 mm) monolithic silica rod HPLC column. After liquid-liquid extraction with diethylether plasma or urine samples were separated with a gradient consisting of solvent A (20% acetonitrile) and solvent B (80% acetonitrile), both in 0.25% acetic acid. The flow rate was 3.5 ml/min and the effluent was monitored by fluorescence with excitation at 230 nm and emission at 410 nm. The retention times for the internal standard (naproxen) and for furosemide were 2.1 and 3.7 min, respectively, and total run time was 8 min. The calibration curves were linear between 7.8 and 1000 ng/ml, and within-assay and between-assay coefficients of variation were <6.5% and <10%, respectively. The proposed assay for furosemide in plasma and urine using monolithic silica rod chromatography is fast, sensitive, and reliable, and, thus, well suited for pharmacokinetic studies.

Pulmonary haemodynamics at rest and during exercise in patients with significant pulmonary vein stenosis after radiofrequency catheter ablation for drug resistant atrial fibrillation

AIMS

Iatrogenic pulmonary vein (PV) stenosis after radiofrequency catheter ablation for atrial fibrillation (AF) is a new pathology in cardiology. The effects of PV stenosis on the pulmonary circulation are not yet known. We provide long-term follow-up data in patients with significant PV stenosis including magnetic resonance imaging (MRI) and Swan Ganz (SG) right heart catheterization.

METHODS AND RESULTS

One hundred and seventeen patients had MRI 12-24 months after the AF ablation procedure. Eleven patients (58+/-7 years, nine males) with significant stenosis (n=9) or occlusion of the proximal PV (n=5) at this follow-up were re-examined using MRI and SG right heart catheterization at rest and during exercise (follow-up time since PV ablation 50+/-15 months). None of these underwent previous PV angioplasty. When compared with prior MRI studies, no significant changes were noted. At rest, no patient had pulmonary hypertension. At 100 W, seven patients had elevated pulmonary artery pressures, three of them probably caused, in part, by left ventricular dysfunction.

CONCLUSION

Significant stenosis/occlusions of one or two PV do not create pulmonary hypertension at rest during long-term follow-up. However, seven of the 11 patients develop pulmonary hypertension during exercise. All three patients with stenosis/occlusions of two PV were affected.