Improved in-hospital outcome for radial access in a large contemporary cohort of primary percutaneous coronary intervention.

BACKGROUND: Randomised controlled trials have shown diverse results for radial access in patients undergoing primary percutaneous coronary intervention (PPCI). Moreover, it is questionable whether radial access improves outcome in patients with cardiogenic shock undergoing PPCI. We aimed to investigate the outcome according to access site in patients with or without cardiogenic shock, in daily clinical practice. METHODS: For the present analysis we included 9,980 patients undergoing PPCI between 2012 and 2018, registered in the multi-centre, nationwide registry on PCI for myocardial infarction (MI). In-hospital mortality, major adverse cardiovascular events (MACE), and net adverse clinical events (NACE) until discharge were compared between 4,498 patients with radial (45%) and 5,482 patients with femoral (55%) access. RESULTS: Radial compared to femoral access was associated with lower in-hospital mortality (3.5% vs. 7.7%; P<0.01). Multivariable logistic regression analysis confirmed reduced in-hospital mortality [odds ratio (OR) 0.57, 95% confidence interval (CI): 0.43 to 0.75]. Furthermore, MACE (OR 0.60, 95% CI: 0.47 to 0.78) as well as NACE (OR 0.59, 95% CI: 0.46 to 0.75) occurred less frequently in patients with radial access. Interaction analysis with cardiogenic shock showed an effect modification, resulting in lower mortality in PCI via radial access in patients without, but no difference in those with cardiogenic shock (OR 1.78, 95% CI: 1.07 to 2.96). CONCLUSIONS: Radial access for patients with acute MI undergoing PPCI is associated with improved survival in a large contemporary cohort of daily practice. However, this beneficial effect is restricted to hemodynamically stable patients.

Dabigatran: patient management in specific clinical settings.

Dabigatran, a direct thrombin inhibitor, is licensed for the prevention of venous thromboembolism after knee and hip replacement, the prevention of stroke and systemic embolism in patients with non-valvular atrial fibrillation and for the treatment of acute venous thromboembolism. As dabigatran has a favourable benefit-risk profile, it is being increasingly used. Dabigatran differs from vitamin K antagonists as regards its pharmacological characteristics and its impact on certain laboratory tests, and also in the lack of a direct antagonist that can reverse dabigatran-induced anticoagulation. In emergency settings such as acute bleeding, emergency surgery, acute coronary syndrome, thrombolysis for ischaemic stroke or overdosing, specific strategies are required. A working group of experts from various disciplines has developed strategies for the management of dabigatran-treated patients in emergency settings.

Duration of the A(H)-A(Md) interval predicts occurrence of AV-block after radiofrequency ablation of the slow pathway.

PURPOSE: Modification of the slow pathway (SP) of the atrio-ventricular node by radiofrequency ablation is the most effective treatment to cure AV nodal reentry tachycardia (AVNRT). However, this therapy may be complicated by AV-block (AVB). We sought to evaluate the predictive value of the A(H)-A(Md) interval-the electrical delay between atrial signals on the His- and the ablation-catheter-upon development of AVB during SP ablation. METHODS: The associations between A(H)-A(Md) interval, occurrence of ventriculo-atrial block (VAB) during junctional activity (JA) and transient or permanent AVB were analyzed retrospectively for 1585 RF applications at the SP in 393 patients diagnosed with AVNRT. The value of A(H)-A(Md) was further tested prospectively in 118 AVNRT patients, who were only ablated at targets with intervals >20 ms. RESULTS: Forty-six RF deliveries resulted in transient or permanent AV-conduction disturbances. Shorter A(H)-A(Md) intervals were associated with the occurrence of VAB during JA (p < 0.001) and AVB (p < 0.001). A(H)-A(Md) was the strongest predictor for VAB or AVB in multivariate regression analyses, followed by the radiological distance between the catheters. In the prospective study, permanent high-degree AVB was not observed when the A(H)-A(Md) at the ablation site was >20 ms. CONCLUSION: The A(H)-A(Md) interval is a better predictor for occurrence of conduction block during ablation for AVNRT than the radiological distance between the His- and the ablation-catheter. The risk of permanent AVB can be minimized, if only sites with an A(H)-A(Md) longer than 20 ms are targeted for ablation.

Safety and effectiveness of levosimendan in patients with predominant right heart failure.

BACKGROUND AND PURPOSE: Levosimendan is a new calcium sensitizer that enhances the contractile force of the myocardium and exhibits additional vasodilating properties. The present study describes the hemodynamic effects of levosimendan in patients with acute predominant right heart failure in need of inotropic therapy. PATIENTS AND METHODS: 18 patients (15 male, age 60 +/- 17 years) with acute heart failure, predominant right ventricular dysfunction, left ventricular ejection fraction (LVEF) < or = 30%, cardiac index (CI) < or = 2.5 l/min/m(2), right atrial pressure (RAP) > or = 10 mmHg, and pulmonary capillary wedge pressure (PCWP) > or = 15 mmHg were investigated. Following a loading dose, levosimendan was administered intravenously for 24 h. RESULTS: After 24 h, CI and left ventricular stroke work index increased from 1.7 +/- 0.4 to 2.3 +/- 0.6 l/min/m(2) (p < 0.001) and 14 +/- 6 to 17.3 +/- 8 g-m/m(2)/beat (p < 0.05), respectively. PCWP and systemic vascular resistance decreased from 25 +/- 7 to 21 +/- 5 mmHg (p < 0.01) and 1,724 +/- 680 to 1,096 +/- 312 dyne * s * cm(-5) (p < 0.0001), respectively. RAP was reduced from 15 +/- 5 to 10 +/- 3 mmHg (p < 0.001), whereas decreases in mean pulmonary artery pressure and pulmonary vascular resistance were not significant. Right ventricular stroke work index (RVSWI) increased from 4.8 +/- 1.8 to 7.6 +/- 3.4 g-m/m(2)/beat (p < 0.01). CONCLUSION: Levosimendan therapy is feasible and improves hemodynamics in patients with acute predominant right heart failure. Augmentation in RVSWI indicates an increase in right ventricular contractility rather than reduction in afterload as a possible pathophysiological mechanism.

Single-beat noninvasive imaging of cardiac electrophysiology of ventricular pre-excitation.

OBJECTIVES: The aim of this study was to determine whether noninvasive imaging of cardiac electrophysiology (NICE) is feasible in patients with Wolff-Parkinson-White (WPW) syndrome in the clinical setting of a catheter laboratory and to test the accuracy of the noninvasively obtained ventricular activation sequences as compared with that of standard invasive electroanatomic mapping. BACKGROUND: NICE of ventricular activation could serve as a useful tool in the treatment of cardiac arrhythmias and might help improve our understanding of arrhythmia mechanisms. METHODS: NICE works by fusing the data from high-resolution electrocardiographic mapping and a model of the patient's cardiac anatomy obtained by magnetic resonance imaging. The ventricular activation sequence was computed with a bidomain theory-based heart model to solve this inverse problem. Noninvasive imaging of cardiac electrophysiology was performed in 7 patients with WPW syndrome undergoing catheter ablation of the accessory pathway. The position error of NICE was defined as the distance between the site of earliest activation computed by NICE and the successful ablation site identified by electroanatomic mapping (CARTO; Biosense Webster, Diamond Bar, California) for normal atrioventricular (AV) conduction as well as for adenosine-induced AV block. RESULTS: The error introduced by geometric coupling of the CARTO data and the NICE model was 5 +/- 3 mm (model discretization 10 mm). All ventricular accessory pathway insertion sites were identified with an accuracy of 18.7 +/- 5.8 mm (baseline) and 18.7 +/- 6.4 mm (adenosine). CONCLUSIONS: The individual cardiac anatomy model obtained for each patient enables accurate noninvasive electrocardiographic imaging of ventricular pre-excitation in patients with WPW syndrome. Noninvasive imaging of cardiac electrophysiology might be used as a complementary noninvasive approach to localize the origin and help identify and understand the underlying mechanisms of cardiac arrhythmias.

Effects of cardiac resynchronization therapy on ventricular repolarization in patients with congestive heart failure.

INTRODUCTION: Biventricular pacing has been shown to improve the clinical status of patients with congestive heart failure, but little is known about its influence on ventricular repolarization. The aim of our study was to evaluate the effect of biventricular pacing on ECG markers of ventricular repolarization in patients with congestive heart failure. METHODS AND RESULTS: Twenty-five patients with congestive heart failure, sinus rhythm (SR), and complete LBBB (6 females; age 61 +/- 8 years; NYHA class II-III; echocardiographic ejection fraction 21 +/- 5%; QRS > or = 130 ms) underwent permanent biventricular DDDR pacemaker implantation. A high-resolution 65-lead body-surface ECG recording was performed at baseline and during right-, left-, and biventricular pacing, and the total 65-lead root mean square curve of the QRST complex and the interlead QT dispersion were assessed. The QRS duration was increased during right (RV)- and left ventricular (LV) pacing (127 +/- 26% and 117 +/- 40%; P < 0.05), as compared to SR (100%) and biventricular pacing (93 +/- 16%; ns). The QTc interval was increased during RV and LV pacing (112 +/- 12% and 114 +/- 14%; P < 0.05) as compared to SR (100%) or biventricular pacing (99 +/- 12%). There was no effect on JT interval during all pacing modes. The T(peak-end) interval was increased during right (120 +/- 34%; P < 0.01) and LV pacing (113 +/- 29%; P < 0.05) but decreased during biventricular pacing (81 +/- 19%; P < 0.01). A similar effect was found for the T(peak-end) integral and the T(peak) amplitude. QT dispersion was increased during right ventricular (129 +/- 16 ms; P < 0.05) and decreased during biventricular pacing (90 +/- 12 ms; P < 0.01), as compared to SR (114 +/- 22 ms). CONCLUSIONS: Using a high-resolution surface ECG, biventricular pacing resulted in a significant reduction of ECG markers of ventricular dispersion of repolarization.

C-reactive protein plasma levels but not factor VII activity predict clinical outcome in patients undergoing elective coronary intervention.

BACKGROUND: Both vascular inflammation as determined by C-reactive protein (CRP) and extrinsic coagulation as measured by factor VII activity (F VII) may predict clinical restenosis rate in patients with stable angina pectoris undergoing elective percutaneous coronary intervention (PCI). HYPOTHESIS: The primary objective of this study was to investigate the associations between baseline CRP levels, F VII activity, and restenosis rate after elective PCI in a 6-month follow-up period. METHODS: This prospective study included 81 patients aged > or = 19 years undergoing PCI for angiographically significant (> or = 70%) stenosis, with or without stenting, and 49 controls. Factor VII activity and CRP were measured in samples collected at angiography and 16-24 h post procedure after overnight fast. Successful PCI was defined as final diameter of < 50% with TIMI 3 flow and no complication within 1 h. After 6 months all patients who had undergone PCI were evaluated via a standardized questionnaire. Clinical restenosis was defined as the occurrence of a major adverse coronary events (MACE), within the follow-up period. RESULTS: Diagnostic angiography led to a significant increase in CRP levels after 16-20 h in patients with discrete CAD (n = 22) but not in patients without any signs of coronary atherosclerosis (n = 27). During a 6-month follow-up after PCI, 17 of 81 (21%) patients developed MACE. Tertiles of CRP levels independently predicted clinical restenosis, as it developed in 33.3% of patients with the highest CRP levels (0.7-4.8 mg/dl), in 16.6% of patients with second tertile CRP levels (0.23-0.69 mg/dl), and in 7.4% of patients with lowest tertile CRP levels (0.0-0.22 mg/dl). There was a significant difference in the restenosis rate between patients from the first and the third tertiles (p = 0.018). Successful PCI was associated with a significant decrease of mean CRP levels after 6 months, whereas PCI in patients suffering from MACE led to no change in CRP levels. There was no association between factor VII activity and clinical outcome after PCI, and F VII activity did not change over a 6-month period. CONCLUSIONS: In patients with stable angina pectoris undergoing elective PCI, increased preprocedural and 6-month follow-up CRP plasma levels are associated with clinical restenosis. Factor VII plasma activity lacks such correlations.

The influence of high versus normal impedance ventricular leads on pacemaker generator longevity.

As pacemaker generator longevity is dependent on current consumption and resistance of the pacing lead, the use of a high impedance pacing lead theoretically results in an extension of battery longevity. Therefore, the effect of high versus standard impedance ventricular leads on generator longevity was studied. In 40 patients (21 women, age 73 +/- 13 years) with a standard dual chamber pacemaker indication, a bipolar standard impedance ventricular lead was implanted in 20 patients, the remaining patients received a bipolar high impedance lead in a randomized fashion. All patients received identical pacemaker generators and atrial leads. The estimated longevity of the generator was calculated automatically by a programmed pacemaker algorithm. After a mean follow-up of 39 +/- 4.8 months, no significant differences were observed with respect to mean pacing and sensing thresholds of the atrial and ventricular leads in both groups. However, the high impedance leads displayed a significantly higher impedance and a significantly lower current drain as compared to standard impedance leads (1,044 +/- 139 vs 585 +/- 90 Omega, and 2.2 +/- 0.4 vs 4.3 +/- 1.1 mA). The extrapolated generator longevity was significantly longer in the high impedance lead group, as compared to the standard impedance lead group (107.3 +/- 8.5 vs 97.6 +/- 9.0 months; P = 0.02). In conclusion, implantation of a high impedance lead for ventricular pacing results in a clinically relevant extension of generator longevity.

Atrial noninvasive activation mapping of paced rhythm data.

INTRODUCTION: Atrial arrhythmias have emerged as a topic of great interest for clinical electrophysiologists. Noninvasive imaging of electrical function in humans may be useful for computer-aided diagnosis and treatment of cardiac arrhythmias, which can be accomplished by the fusion of data from ECG mapping and magnetic resonance imaging (MRI). METHODS AND RESULTS: In this study, a bidomain-theory-based surface heart model activation time (AT) imaging approach was applied to paced rhythm data from four patients. Pacing sites were the right superior pulmonary vein, left inferior pulmonary vein, left superior pulmonary vein, coronary sinus, posterior wall of right atrium, and high right atrium. For coronary sinus pacing, the AT pattern of the right atrium was compared with a CARTO map. The root mean square error between CARTO geometry (85 nodal points) and the surface model of the right atrium was 8.6 mm. The correlation coefficient of the noninvasively obtained AT map of the right atrium and the CARTO map was 0.76. All pulmonary vein pacing sites were identified. The reconstructed pacing site of right posterior atrial pacing correlates with the invasively determined pacing catheter position with a localization distance of 4 mm. CONCLUSION: The individual anatomic model of the atria of each patient enables accurate noninvasive AT imaging within the atria, resulting in a localization error for the pacing sites within 10 mm. Our findings may have implications for imaging of atrial activity in patients with focal arrhythmias or focal triggers.

Electrocardiographic imaging of atrial and ventricular electrical activation.

Inverse electrocardiography has been developing for several years. By combining measurements obtained by electrocardiographic body surface mapping with three-dimensional anatomical data, one can non-invasively image the electrical activation sequence in the human heart. In this study, an imaging approach that uses a bidomain theory-based surface heart model was applied to single-beat data of atrial and ventricular activation. We found that for sinus and paced rhythms, the sites of early activation and the areas with late activation were estimated with sufficient accuracy. In particular, for focal arrhythmias, this model-based imaging approach might allow the guidance and evaluation of antiarrhythmic interventions, for instance, in case of catheter ablation or drug therapy.

Global P wave duration on the 65-lead ECG: single-site and dual-site pacing in the structurally normal human atrium.

INTRODUCTION: Pacing is believed to prevent atrial fibrillation by reducing atrial activation time. Exact correlation between P wave duration (PWD) on surface ECG and endocardial atrial activation time is still unexplored. METHODS AND RESULTS: In 15 patients without structural heart disease (9 women, age 45 +/- 14 years), single site [high right atrium (HRA), coronary sinus ostium (CSos), distal CS (CSd), high RA septum (Bachmann's bundle, BB)] and dual-site pacing (various combinations) was performed after ablation of supraventricular tachycardia. A 65-lead surface ECG was recorded simultaneously. Endocardial atrial activation time was measured off-line (stimulus - last bipolar recording), and the respective PWD was assessed using the root mean square and 65-channel summary plots. PWD during pacing from BB was significantly shorter (96 +/- 12 msec) than during HRA (121 +/- 15 msec), CSos (108 +/- 9 msec), and CSd pacing (126 +/- 14 msec; P < 0,01, respectively). PWD during dual-site pacing (HRA+BB, 91 +/- 14 msec; HRA+CSos, 96 +/- 7 msec; HRA+CSd, 90 +/- 7 msec; BB+CSd, 96 +/- 12 msec) was not significantly shorter than during pacing from BB. Correlation between endocardial atrial activation time and PWD was 0.83. CONCLUSION: PWD during single-site and dual-site atrial pacing represents endocardial atrial activation time and can be measured precisely using the 65-lead surface ECG. The fact that high septal pacing results in the shortest PWD may have implications for preventive pacing in patients with atrial fibrillation.