Evaluation of pulse wave velocity for predicting major adverse cardiovascular events in post-infarcted patients; comparison of oscillometric and MRI methods.

Increased aortic pulse wave velocity (PWV) has been proved as a strong predictor of major adverse cardiovascular events (MACE) in patients after myocardial infarction (MI). Due to the various technical approaches the level of high PWV values show significant differences. We evaluated the cut-off PWV values for MACE prediction using cardiac magnetic resonance imaging (CMR) and oscillometric methods for validating the prognostic value of high PWV in post-infarcted patients. Phase contrast imaging (PCI) and oscillometric based Arteriograph (AG) were compared in this 6 years follow-up study, including 75 consecutive patients of whom 49 suffered previous ST-elevation myocardial infarction (STEMI). Patients received follow-up for MACE comprising all-cause death, non-fatal MI, ischemic stroke, hospitalization for heart failure and coronary revascularization. An acceptable agreement and significant correlation (rho: 0.332, p < 0.01) was found between AG and CMR derived PWV values. The absolute values, however, were significantly higher for AG (median (IQR): 10.4 (9.2-11.9) vs 6.44 (5.64-7.5) m/s; p < 0.001). Totally 51 MACE events occurred during the 6 years follow-up period in post-infarcted patients. Kaplan-Meier analysis in both methods showed significantly lower event-free survival in case of high PWV (CMR: >6.47 m/s, AG: >9.625 m/s, p < 0.001, respectively). Multivariate Cox regression revealed PWV as a predictor of MACE (PWV CMR hazard ratio (HR): 1.31 (CI: 1.1-1.7), PWV AG HR: 1.24 (CI: 1.0-1.5), p < 0.05, respectively). Increased PWV derived by AG and CMR methods are feasible for MACE prediction in post-infarcted patients. However, adjusted cut-off values of PWV are recommended for different techniques to improve individual risk stratification.

Ictal asystole: A systematic review.

OBJECTIVE: To comprehensively analyze ictal asystole (IA) on a large number of subjects. METHODS: We performed a systematic review of case report studies of patients diagnosed with IA (1983-2016). Each included case was characterized with respect to patient history, IA seizure characteristics, diagnostic workup, and therapy. In addition, comparative analyses were also carried out: two alignments were developed based on the delay between epilepsy onset and IA onset ("new-onset" if <1 year, "late-onset" if ≥1 year) and asystole duration (asystole was "very prolonged" if lasted >30 s). RESULTS: One hundred fifty-seven cases were included. All patients had focal epilepsy. In 7% of cases IA developed during a secondary generalized tonic-clonic seizure. Both the seizure-onset zone and the focal seizure activity at asystole beginning were usually temporal (p < 0.001 and p = 0.001, respectively) and were lateralized to the left hemisphere in 62% (p = 0.005 and p = 0.05, respectively). Asystole duration was 18 ± 14 s (mean±SD) (range 3-96 s); 73% of patients had late-onset, 27% had new-onset IA. Compared to late-onset IA, new-onset IA was associated with female gender (p = 0.023), preexisting heart condition (p = 0.014), focal seizure activity at asystole beginning (p = 0.012), normal neuroimaging (p = 0.013), normal interictal EEG (p < 0.001), auditory aura (p = 0.012), and drug-responsive epilepsy (p < 0.001). "Very prolonged" asystole was associated with secondary generalized tonic-clonic seizures (p = 0.003) and tended to occur in extratemporal lobe seizures (p = 0.074). No IA-related death was reported. SIGNIFICANCE: Characteristics considered to be typical of IA (focal, left temporal seizures appearing on grounds of a long-lasting, intractable epilepsy) seem only partially legitimate. We suggest that in new-onset IA, female gender and a preexisting heart condition could serve as predispositions in an otherwise benign epilepsy. We speculate that in late-onset IA, male-predominant changes in neuronal networks in chronic, intractable epilepsy and an accompanying autonomic dysregulation serve as facilitating factors.

Age-independent myocardial infarct quantification by signal intensity percent infarct mapping in swine.

PURPOSE: To test whether signal intensity percent infarct mapping (SI-PIM) accurately determines the size of myocardial infarct (MI) regardless of infarct age. MATERIALS AND METHODS: Forty-five swine with reperfused MI underwent 1.5T late gadolinium enhancement (LGE) magnetic resonance imaging (MRI) after bolus injection of 0.2 mmol/kg Gd(DTPA) on days 2-62 following MI. Animals were classified into acute, healing, and healed groups by pathology. Infarct volume (IV) and infarct fraction (IF) were determined by two readers, using binary techniques (including 2-5 standard deviations [SD] above the remote, and full-width at half-maximum) and the SI-PIM method. Triphenyl-tetrazolium-chloride staining (TTC) was performed as reference. Bias (percent under/overestimation of IV relative to TTC) of each quantification method was calculated. Bland-Altman analysis was done to test the accuracy of the quantification methods, while intraclass correlation coefficient (ICC) analysis was done to assess intra- and interobserver agreement. RESULTS: Bias of the MRI quantification methods do not depend on the age of the MI. Full-width at half-maximum (FWHM) and SI-PIM gave the best estimate of MI volume determined by the reference TTC (P-values for the FWHM and SI-PIM methods were 0.183, 0.26, 0.95, and 0.073, 0.091, 0.73 in Group 1, Group 2, and Group 3, respectively), while using any of the binary thresholds of 2-4 SDs above the remote myocardium showed significant overestimation. The 5 SD method, however, provided similar IV compared to TTC and was shown to be independent of the size and age of MI. ICC analysis showed excellent inter- and intraobserver agreement between the readers. CONCLUSION: Our results indicate that the SI-PIM method can accurately determine MI volume regardless of the pathological stage of MI. Once tested, it may prove to be useful for the clinic.

MR-IMPACT II: Magnetic Resonance Imaging for Myocardial Perfusion Assessment in Coronary artery disease Trial: perfusion-cardiac magnetic resonance vs. single-photon emission computed tomography for the detection of coronary artery disease: a comparative multicentre, multivendor trial.

AIMS: Perfusion-cardiac magnetic resonance (CMR) has emerged as a potential alternative to single-photon emission computed tomography (SPECT) to assess myocardial ischaemia non-invasively. The goal was to compare the diagnostic performance of perfusion-CMR and SPECT for the detection of coronary artery disease (CAD) using conventional X-ray coronary angiography (CXA) as the reference standard. METHODS AND RESULTS: In this multivendor trial, 533 patients, eligible for CXA or SPECT, were enrolled in 33 centres (USA and Europe) with 515 patients receiving MR contrast medium. Single-photon emission computed tomography and CXA were performed within 4 weeks before or after CMR in all patients. The prevalence of CAD in the sample was 49%. Drop-out rates for CMR and SPECT were 5.6 and 3.7%, respectively (P = 0.21). The primary endpoint was non-inferiority of CMR vs. SPECT for both sensitivity and specificity for the detection of CAD. Readers were blinded vs. clinical data, CXA, and imaging results. As a secondary endpoint, the safety profile of the CMR examination was evaluated. For CMR and SPECT, the sensitivity scores were 0.67 and 0.59, respectively, with the lower confidence level for the difference of +0.02, indicating superiority of CMR over SPECT. The specificity scores for CMR and SPECT were 0.61 and 0.72, respectively (lower confidence level for the difference: -0.17), indicating inferiority of CMR vs. SPECT. No severe adverse events occurred in the 515 patients. CONCLUSION: In this large multicentre, multivendor study, the sensitivity of perfusion-CMR to detect CAD was superior to SPECT, while its specificity was inferior to SPECT. Cardiac magnetic resonance is a safe alternative to SPECT to detect perfusion deficits in CAD.

The Influence of Different Multipolar Mapping Catheter Types on Procedural Outcomes in Patients Undergoing Pulmonary Vein Isolation for Atrial Fibrillation.

(1) Background: During pulmonary vein isolation (PVI) for atrial fibrillation (AF), multipolar mapping catheters (MMC) are often used. We aimed to compare the procedural outcomes of two MMCs, specifically a circular-shaped and a five-spline-shaped MMC. (2) Methods: We enrolled 70 consecutive patients in our prospective, observational trial undergoing PVI procedures for paroxysmal AF. The initial 35 patients underwent PVI procedures with circular-shaped MMC guidance (Lasso Group), and the procedures for the latter 35 cases were performed using five-spline-shaped MMC (PentaRay Group). (3) Results: No significant differences were identified between the two groups in total procedure time (80.2 ± 17.7 min vs. 75.7 ± 14.8 min, p = 0.13), time from femoral vein puncture to the initiation of the mapping (31.2 ± 7 min vs. 28.9 ± 6.8, p = 0.80), mapping time (8 (6; 13) min vs. 9 (6.5; 10.5) min, p = 0.73), duration between the first and last ablation (32 (30; 36) min vs. 33 (26; 40) min, p = 0.52), validation time (3 (2; 4) min vs. 3 (1; 5) min, p = 0.46), first pass success rates (89% vs. 91%, p = 0.71), left atrial dwelling time (46 (37; 53) min vs. 45 (36.5; 53) min, p = 0.56), fluoroscopy data (time: 150 ± 71 s vs. 143 ± 56 s, p = 0.14; dose: 6.7 ± 4 mGy vs. 7.4 ± 4.4 mGy, p = 0.90), total ablation time (1187 (1063; 1534) s vs. 1150.5 (1053; 1393.5) s, p = 0.49), the number of ablations (78 (73; 93) vs. 83 (71.3; 92.8), p = 0.60), and total ablation energy (52,300 (47,265; 66,804) J vs. 49,666 (46,395; 56,502) J, p = 0.35). (4) Conclusions: This study finds comparable procedural outcomes bet-ween circular-shaped and five-spline-shaped MMCs for PVI in paroxysmal AF, supporting their interchangeability in clinical practice for anatomical mapping.

Comparison of Conventionally Performed and Intracardiac Echocardiography Guided Catheter Ablation of Atrioventricular Node in Patients with Permanent Atrial Fibrillation-A Retrospective Single-Center Study.

Background: Atrioventricular node (AVN) ablation is an effective treatment for atrial fibrillation (AF) with uncontrolled ventricular rates despite maximal pharmacological treatment. Intracardiac echocardiography (ICE) can help with visualizing structures, positioning catheters, and guiding the ablation procedure. We compared only fluoroscopy-guided and ICE-guided AVN ablation regarding patients with permanent AF. Methods: Sixty-two consecutive patients underwent AVN ablation were enrolled in our retrospective single-center study (ICE group: 28 patients, Standard group: 34 patients). Procedural data, acute and long-term success rate, and complications were analyzed. Results: ICE guidance for AVN ablation significantly reduced fluoroscopy time (0.30 [0.06; 0.85] min vs. 7.95 [3.23; 6.59] min, p < 0.01), first-to-last ablation time (4 [2; 16.3] min vs. 26.5 [2.3; 72.5] min, p = 0.02), and in-procedure time (40 [34; 55] min vs. 60 [45; 110], p = 0.02). There was no difference in either the total ablation time (199 [91; 436] s vs. 294 [110; 659] s, p = 0.22) or in total ablation energy (8272 [4004; 14,651] J vs. 6065 [2708; 16,406] J, p = 0.28). The acute success rate was similar (ICE: 100% vs. Standard: 94%, p = 0.49) between the groups. Conclusions: In our retrospective trial, ICE-guided AVN ablation reduced fluoroscopy time, procedure time, and first-to-last ablation time. There was no difference in ablation time, total ablation energy, acute and long-term success, and complication rate.

Initial experience with zero-fluoroscopy pulmonary vein isolation in patients with atrial fibrillation: single-center observational trial.

Pulmonary vein isolation (PVI) stands as a widely practiced cardiac ablation procedure on a global scale, conventionally guided by fluoroscopy. The concurrent application of electroanatomical mapping systems (EAMS) and intracardiac echocardiography offers a means to curtail radiation exposure. This study aimed to compare procedural outcomes between conventional and our initial zero-fluoroscopy cases in patients with paroxysmal or persistent atrial fibrillation (AF), undergoing point-by-point PVI. Our prospective observational study included 100 consecutive patients with AF who underwent point-by-point radiofrequency PVI. The standard technique was used in the first 50 cases (Standard group), while the fluoroless technique was used in the subsequent 50 patients (Zero group). The zero-fluoroscopy approach exhibited significantly shorter procedural time (59.6 ± 10.7 min vs. 74.6 ± 13.2 min, p < 0.0001), attributed to a reduced access time (17 [16; 20] min vs. 31 [23; 34.5] min, p < 0.001). Comparable results were found for the number of RF applications, total ablation energy, and left atrial dwelling time. In the Zero group, all procedures were achieved without fluoroscopy, resulting in significantly lower fluoroscopy time (0 [0; 0] sec vs. 132 [100; 160] sec, p < 0.0001) and dose (0 [0; 0] mGy vs. 4.8 [4.1; 8.2] mGy, p < 0.0001). The acute success rate was 100%, with no major complications. Zero-fluoroscopy PVI is feasible, safe, and associated with shorter procedure times compared to the standard approach, even in cases without prior experience in zero-fluoroscopy PVI.

Embozene™ microspheres induced nonreperfused myocardial infarction in an experimental swine model.

OBJECTIVES: To develop a magnetic resonance imaging (MRI) compatible, percutaneous technique for the generation of nonreperfused myocardial infarct (MI). BACKGROUND: Modeling nontreated MI has major importance in the development and preclinical testing of new therapeutic strategies for patients missing the time window suitable for revascularization following MI. METHODS: In 31 male swine, nonreperfused MI was generated by permanent occlusion of either the LAD or LCX coronary artery using 900 µm Embozene™ microspheres. Animals were monitored for 90 min postocclusion. Surviving animals were followed up for 2 (n = 6), 4 (n = 6), 14 (n = 6), or 56 (n = 6) days. At the end of the planned study session, contrast enhanced MRI, triphenyl-tetrazolium-chloride staining, and microscopic histopathology were carried out. RESULTS: The mortality rate in this study was 22.6%. Intraoperative arrhythmias occurred in 14 cases: premature ventricular complexes with (5) or without (3) ventricular tachycardia, 2nd degree atrio-ventricular block (1), and ventricular fibrillation (6). MRI, TTC, and histology confirmed the existence of MI in every case. Macroscopic pathology showed that the microspheres caused a practically total occlusion at the epicardial level of the coronary artery. Multiple infarcts were detected in one case, probably due to unintentional reflux of the microspheres. Microspheres retained in the coronary arteries did not cause any MRI artifact. CONCLUSIONS: The generation of nonreperfused MI is feasible by percutaneous injection of Embozene into the coronary artery system. The MI model thus obtained is suitable for the purposes of MRI experiments.

Evaluation of experimental myocardial infarction models via electromechanical mapping and magnetic resonance imaging.

The diagnostic characteristics of electromechanical mapping (EMM) were evaluated in porcine myocardial infarction (MI) models with the parallel application of cardiac magnetic resonance imaging (cMRI) from the aspect of different pathophysiology and localization. Balloon occlusion in the left anterior descending coronary artery (LAD balloon group) or coil deployment in the LAD (LAD coil group) or circumflex artery (Cx coil group) was applied percutaneously in 16 domestic pigs. Regional left ventricular viability data were captured via cMRI and EMM. The unipolar voltage (UV) value was significantly decreased in segments containing transmural and subendocardial late enhancement compared with viable segments in the LAD balloon, LAD coil, and Cx coil groups. Receiver operating characteristic analysis revealed area under the curve values of 0.809 and 0.691 in the LAD infarct territory, and 0.864 and 0.855 in the Cx infarct territory for the UV compared with cMRI viability results as transmural late enhancement or viable tissue and subendocardial late enhancement or viable tissue, respectively. In conclusion, the UV value detected the presence of scar tissue with differential transmural extent and which represented proper diagnostic features both in the reperfused and nonreperfused models. This data could provide additional benefit in the clinical use of EMM for diagnostic purposes.

Electroanatomical Mapping System-Guided vs. Intracardiac Echocardiography-Guided Slow Pathway Ablation: A Randomized, Single-Center Trial.

Radiofrequency (RF) catheter ablation is an effective treatment option for targeting the slow pathway (SP) in atrioventricular nodal reentry tachycardia (AVNRT). Previous data suggested that using intracardiac echocardiography (ICE) guidance could improve procedural outcomes when compared to using fluoroscopy alone. In this prospective study, we aimed to compare the effectiveness of an electroanatomical mapping system (EAMS)-guided approach with an ICE-guided approach for SP ablation. Eighty patients undergoing SP ablation for AVNRT were randomly assigned to either the ICE-guided or EAMS-guided group. If the procedural endpoint was not achieved after 8 RF applications; patients were allowed to crossover to the ICE-guided group. The ICE-guided approach reduced the total procedure time (61.0 (56.0; 66.8) min vs. 71.5 (61.0; 80.8) min, p < 0.01). However, the total fluoroscopy time was shorter (0 (0-0) s vs. 83.5 (58.5-133.25) s, p < 0.001) and the radiation dose was lower (0 (0-0) mGy vs. 3.3 (2.0-4.7) mGy, p < 0.001) with EAMS-guidance. The ICE-guided group had a lower number of RF applications (4 (3-5) vs. 5 (3.0-7.8), p = 0.03) and total ablation time (98.5 (66.8-186) s vs. 136.5 (100.5-215.8) s, p = 0.02). Nine out of 40 patients (22.5%) in the EAMS-guided group crossed over to the ICE-guided group, and they were successfully treated with similar RF applications in terms of number, time, and energy compared to the ICE-guided group. There were no recurrences during the follow-up period. In conclusion, the utilization of ICE guidance during SP ablation has demonstrated notable reductions in procedural time and RF delivery when compared to procedures guided by EAMS. In challenging cases, an early switch to ICE-guided ablation may be the optimal choice for achieving successful treatment.