Advanced CT measures of coronary artery disease with intermediate stenosis in patients with severe aortic valve stenosis.

BACKGROUND: Coronary artery disease (CAD) and severe aortic valve stenosis (AS) frequently coexist. While pre-transcatheter aortic valve replacement (TAVR) computed tomography angiography (CTA) allows to rule out obstructive CAD, interpreting hemodynamic significance of intermediate stenoses is challenging. This study investigates the incremental value of CT-derived fractional flow reserve (CT-FFR), quantitative coronary plaque characteristics (e.g., stenosis degree, plaque volume, and composition), and peri-coronary adipose tissue (PCAT) density to detect hemodynamically significant lesions among those with AS and CAD. MATERIALS AND METHODS: We included patients with severe AS and intermediate coronary lesions (20-80% diameter stenosis) who underwent pre-TAVR CTA and invasive coronary angiogram (ICA) with resting full-cycle ratio (RFR) assessment between 08/16 and 04/22. CTA image analysis included assessment of CT-FFR, quantitative coronary plaque analysis, and PCAT density. Coronary lesions with RFR ≤ 0.89 indicated hemodynamic significance as reference standard. RESULTS: Overall, 87 patients (age 77.9 ± 7.4 years, 38% female) with 95 intermediate coronary artery lesions were included. CT-FFR showed good discriminatory capacity (area under receiver operator curve (AUC) = 0.89, 95% confidence interval (CI) 0.81-0.96, p < 0.001) to identify hemodynamically significant lesions, superior to anatomical assessment, plaque morphology, and PCAT density. Plaque composition and PCAT density did not differ between lesions with and without hemodynamic significance. Univariable and multivariable analyses revealed CT-FFR as the only predictor for functionally significant lesions (odds ratio 1.28 (95% CI 1.17-1.43), p < 0.001). Overall, CT-FFR ≤ 0.80 showed diagnostic accuracy, sensitivity, and specificity of 88.4% (95%CI 80.2-94.1), 78.5% (95%CI 63.2-89.7), and 96.2% (95%CI 87.0-99.5), respectively. CONCLUSION: CT-FFR was superior to CT anatomical, plaque morphology, and PCAT assessment to detect functionally significant stenoses in patients with severe AS. CLINICAL RELEVANCE STATEMENT: CT-derived fractional flow reserve in patients with severe aortic valve stenosis may be a useful tool for non-invasive hemodynamic assessment of intermediate coronary lesions, while CT anatomical, plaque morphology, and peri-coronary adipose tissue assessment have no incremental or additional benefit. These findings might help to reduce pre-transcatheter aortic valve replacement invasive coronary angiogram. KEY POINTS: • Interpreting the hemodynamic significance of intermediate coronary stenoses is challenging in pre-transcatheter aortic valve replacement CT. • CT-derived fractional flow reserve (CT-FFR) has a good discriminatory capacity in the identification of hemodynamically significant coronary lesions. • CT-derived anatomical, plaque morphology, and peri-coronary adipose tissue assessment did not improve the diagnostic capability of CT-FFR in the hemodynamic assessment of intermediate coronary stenoses.

Baroreflex activation therapy reduces frequency and duration of hypertension-related hospitalizations in patients with resistant hypertension.

PURPOSE: Baroreflex activation therapy (BAT) has been shown to lower blood pressure in patients with resistant hypertension. The purpose of this study was to analyze whether this translates into a reduction of more relevant clinical endpoints. METHODS: Patients with resistant hypertension were treated with the second-generation BAT system. Records on hospitalization (dates of admission and discharge, main diagnosis) were obtained from medical insurance companies. RESULTS: Records on hospitalization were available for a period of 1 year before BAT in two patients and 2 years in 22 patients. The total number of hospitalizations per patient was 3.3 ± 3.5/year before BAT and 2.2 ± 2.7/year after BAT (p = 0.03). Hospitalizations related to hypertension were significantly decreased from 1.5 ± 1.6/year before BAT to 0.5 ± 0.9/year after BAT (p < 0.01). The cumulative duration of hypertension-related hospital stays was significantly reduced from 8.0 ± 8.7 days/year before BAT to 1.8 ± 4.8 days/year after BAT (p < 0.01). Office cuff blood pressure was 183 ± 27 mmHg over 102 ± 17 mmHg under 6.6 ± 2.0 antihypertensive drugs before BAT and 157 ± 32 mmHg over 91 ± 20 mmHg (both p < 0.01) under 5.9 ± 1.9 antihypertensive drugs (p = 0.09 for number of drugs) at latest follow-up. Daytime ambulatory blood pressure was 164 ± 21 mmHg over 91 ± 14 mmHg before BAT and 153 ± 21 mmHg (p = 0.03) over 89 ± 15 mmHg (p = 0.56) at latest follow-up. Heart rate was 75 ± 16 bpm before BAT and 72 ± 12 bpm at latest follow-up (p = 0.35). CONCLUSIONS: Rate and duration of hypertension-related hospitalizations in patients with severe resistant hypertension were lowered after BAT. Whether the response is mediated through improvements in blood pressure control requires further studies.

In Vitro Grown Micro-Tissues for Cardiac Cell Replacement Therapy in Vivo.

BACKGROUND/AIMS: Different approaches have been considered to improve heart reconstructive medicine and direct delivery of pluripotent stem cell-derived cardiomyocytes (PSC-CMs) appears to be highly promising in this context. However, low cell persistence post-transplantation remains a bottleneck hindering the approach. Here, we present a novel strategy to overcome the low engraftment of PSC-CMs during the early post-transplantation phase into the myocardium of both healthy and cryoinjured syngeneic mice. METHODS: Adult murine bone marrow mesenchymal stem cells (MSCs) and PSC-CMs were co-cultured on thermo-responsive polymers and later detached through temperature reduction, resulting in the protease-free generation of cell clusters (micro-tissues) composed of both cells types. Micro-tissues were transplanted into healthy and cryo-injured murine hearts. Short term cell retention was quantified by real-time-PCR. Longitudinal cell tracking was performed by bioluminescence imaging for four weeks. Transplanted cells were further detected by immunofluorescence staining of tissue sections. RESULTS: We demonstrated that in vitro grown micro-tissues consisting of PSC-CMs and MSCs can increase cardiomyocyte retention by >10fold one day post-transplantation, but could not fully rescue a further cell loss between day 1 and day 2. Neutrophil infiltration into the transplanted area was detected in healthy hearts and could be attributed to the cellular implantation rather than tissue damage exerted by the transplantation cannula. Injected PSC-CMs were tracked and successfully detected for up to four weeks by bioluminescence imaging. CONCLUSION: This approach demonstrated that in vitro grown micro-tissues might contribute to the development of cardiac cell replacement therapies.

Myeloperoxidase Mediates Postischemic Arrhythmogenic Ventricular Remodeling.

RATIONALE: Ventricular arrhythmias remain the leading cause of death in patients suffering myocardial ischemia. Myeloperoxidase, a heme enzyme released by polymorphonuclear neutrophils, accumulates within ischemic myocardium and has been linked to adverse left ventricular remodeling. OBJECTIVE: To reveal the role of myeloperoxidase for the development of ventricular arrhythmias. METHODS AND RESULTS: In different murine models of myocardial ischemia, myeloperoxidase deficiency profoundly decreased vulnerability for ventricular tachycardia on programmed right ventricular and burst stimulation and spontaneously as assessed by ECG telemetry after isoproterenol injection. Experiments using CD11b/CD18 integrin-deficient (CD11b-/-) mice and intravenous myeloperoxidase infusion revealed that neutrophil infiltration is a prerequisite for myocardial myeloperoxidase accumulation. Ventricles from myeloperoxidase-deficient (Mpo-/-) mice showed less pronounced slowing and decreased heterogeneity of electric conduction in the peri-infarct zone than wild-type mice. Expression of the redox-sensitive gap junctional protein Cx43 (Connexin 43) was reduced in the peri-infarct area of wild-type compared with Mpo-/- mice. In isolated wild-type cardiomyocytes, Cx43 protein content decreased on myeloperoxidase/H2O2 incubation. Mapping of induced pluripotent stem cell-derived cardiomyocyte networks and in vivo investigations linked Cx43 breakdown to myeloperoxidase-dependent activation of matrix metalloproteinase 7. Moreover, Mpo-/- mice showed decreased ventricular postischemic fibrosis reflecting reduced accumulation of myofibroblasts. Ex vivo, myeloperoxidase was demonstrated to induce fibroblast-to-myofibroblast transdifferentiation by activation of p38 mitogen-activated protein kinases resulting in upregulated collagen generation. In support of our experimental findings, baseline myeloperoxidase plasma levels were independently associated with a history of ventricular arrhythmias, sudden cardiac death, or implantable cardioverter-defibrillator implantation in a cohort of 2622 stable patients with an ejection fraction >35% undergoing elective diagnostic cardiac evaluation. CONCLUSIONS: Myeloperoxidase emerges as a crucial mediator of postischemic myocardial remodeling and may evolve as a novel pharmacological target for secondary disease prevention after myocardial ischemia.

Combination of a subcutaneous ICD in a patient with a baroreceptor activation device: Feasibility, safety, and precautions: A Case Report.

We present a case of a patient with a baroreflex activation therapy (BAT) receiving a subcutaneous implantable cardioverter defibrillator (S-ICD). We anticipated two possible hazardous interactions between the two devices. Stimulation by the BAT could be adjudicated as noise and result in underdetection of ventricular arrhythmias or it might be misinterpreted as ventricular arrhythmias and lead to inappropriate shocks. Postop ensing occurred, the upper limit of pulse width of the BAT was limited because of noise detection by the S-ICD, but the upper limit of amplitude was limited by patient's discomfort. In this patient, the combination of a BAT and an S-ICD was safe.

Improvement of Left Ventricular Ejection Fraction by Baroreflex Activation Therapy in a Young Man with Dilated Cardiomyopathy.

The progression of heart failure with reduced ejection fraction is promoted by sympathovagal imbalance. Baroreflex activation therapy (BAT) by the electrical stimulation of baroreceptors at the carotid sinus significantly improved exercise capacity and NT-proBNP levels in a randomized trial; however, no significant difference in left ventricular ejection fraction (LV-EF) between groups was found. Here, we report the case of a 30-year-old man with a long history of dilated cardiomyopathy and severely reduced LV-EF despite optimal medical therapy, who was treated with BAT since October 2014 and showed a remarkable improvement in both symptoms and LV-EF under this treatment.

Baroreflex Activation Therapy in Heart Failure With Reduced Ejection Fraction: Available Data and Future Perspective.

Progression of heart failure with reduced ejection fraction (HFrEF) is promoted by sympathovagal imbalance. Baroreflex activation therapy, i.e., electrical stimulation of baroreceptors at the carotid sinus, can restore sympathovagal balance. Large animal studies of baroreflex activation therapy revealed improvements in cardiac function, susceptibility to ventricular arrhythmias, and a survival benefit as compared to untreated controls. Recently, the first randomized and controlled trial of optimal medical and device therapy alone or plus baroreflex activation therapy in patients suffering from HFrEF was published. It demonstrated a reasonable safety profile in this severely ill patient population. Moreover, the study found significant improvements in New York Heart Association class, quality of life, 6-min walk distance, and NT-proBNP levels. This review provides an overview on baroreflex activation therapy for the treatment of HFrEF-from the concept and preclinical findings to most recent clinical data and upcoming trials.

Electrophysiological characteristics of embryonic stem cell-derived cardiomyocytes are cell line-dependent.

BACKGROUND: Modelling of cardiac development, physiology and pharmacology by differentiation of embryonic stem cells (ESCs) requires comparability of cardiac differentiation between different ESC lines. To investigate whether the outcome of cardiac differentiation is consistent between different ESC lines, we compared electrophysiological properties of ESC-derived cardiomyocytes (ESC-CMs) of different murine ESC lines. METHODS: Two wild-type (D3 and R1) and two transgenic ESC lines (D3/aPIG44 and CGR8/AMPIGX-7) were differentiated under identical culture conditions. The transgenic cell lines expressed enhanced green fluorescent protein (eGFP) and puromycin-N-acetyltransferase under control of the cardiac specific α-myosin heavy chain (αMHC) promoter. Action potentials (APs) were recorded using sharp electrodes and multielectrode arrays in beating clusters of ESC-CMs. RESULTS: Spontaneous AP frequency and AP duration (APD) as well as maximal upstroke velocity differed markedly between unpurified CMs of the four ESC lines. APD heterogeneity was negligible in D3/aPIG44, moderate in D3 and R1 and extensive in CGR8/AMPIGX-7. Interspike intervals calculated from long-term recordings showed a high degree of variability within and between recordings in CGR8/AMPIGX-7, but not in D3/aPIG44. Purification of the αMHC+ population by puromycin treatment posed only minor changes to APD in D3/aPIG44, but significantly shortened APD in CGR8/AMPIGX-7. CONCLUSION: Electrophysiological properties of ESC-CMs are strongly cell line-dependent and can be influenced by purification of cardiomyocytes by antibiotic selection. Thus, conclusions on cardiac development, physiology and pharmacology derived from single stem cell lines have to be interpreted carefully.

Baroreflex activation therapy in patients with pre-existing implantable cardioverter-defibrillator: compatible, complementary therapies.

AIMS: The Neo™ System (CVRx) is an implantable device, CE certified for the treatment of resistant hypertension and investigationally used to treat systolic heart failure by electrical stimulation of the carotid baroreceptors. It is unknown whether interaction might exist between the Neo System and implantable cardioverter-defibrillators (ICDs). METHODS AND RESULTS: Compatibility of the Neo device was tested in seven consecutive patients with pre-existing ICDs. Intra- and post-operative testing was completed with ICD and Neo settings programmed to provoke interaction. Intracardiac electrograms were printed to determine interaction with the ICD. Interaction testing during implantation and follow-up showed that there was no device-device interaction. No interaction was observed at maximum atrial and ventricular sensitivity settings and maximum Neo output settings. CONCLUSION: Combined therapy with the Neo device and at least in this study reported that transvenous ICD systems can be performed safely.

Frailty, periinterventional complications and outcome in patients undergoing percutaneous mitral and tricuspid valve repair.

BACKGROUND: Frailty is common in elderly and multimorbid patients and associated with increased vulnerability to stressors. METHODS: In a single centre study frailty according to Fried criteria was assessed in consecutive patients before transcatheter mitral and tricuspid valve repair. Postprocedural infections, blood transfusion and bleeding and renal failure were retrospectively assessed from records. Median follow-up time for survival was 560 days (IQR: 363 to 730 days). RESULTS: 90% of 626 patients underwent mitral valve repair, 5% tricuspid valve repair, and 5% simultaneous mitral and tricuspid valve repair. 47% were classified as frail. Frailty was associated with a significantly increased frequency of bleeding (16 vs 10%; p = 0.016), blood transfusions (9 vs 3%; p = < 0.001) and infections (18 vs 10%; p = 0.006), but not with acute kidney injury (20 vs 20%; p = 1.00). Bleeding and infections were associated with longer hospital stays, with a more pronounced effect in frail patients (interaction test p < 0.05, additional 3.2 and 4.1 days in frail patients, respectively). Adjustment for the occurrence of complications did not attenuate the increased risk of mortality associated with frailty (HR 2.24 [95% CI 1.62-3.10]; p < 0.001). CONCLUSIONS: Bleeding complications and infections were more frequent in frail patients undergoing transcatheter mitral and tricuspid valve repair and partly explained the longer hospital stay. Albeit some of the complications were associated with higher long-term mortality, this did not explain the strong association between frailty and mortality. Further research is warranted to explore interventions targeting periprocedural complications to improve outcomes in this vulnerable population.

Disentangling Heart Failure and Physical Frailty: Prospective Study of Patients Undergoing Percutaneous Mitral Valve Repair.

BACKGROUND: Frailty and heart failure share pathophysiology and clinical characteristics. OBJECTIVES: The aim of this study was to analyze the contribution of heart failure to the physical frailty phenotype by examining patients with heart failure before and after percutaneous mitral valve repair (PMVR). METHODS: Frailty according to the Fried criteria (weight loss, weakness, exhaustion, slowness, and low activity) was assessed in consecutive patients before and 6 weeks after PMVR. RESULTS: A total of 118 of 258 patients (45.7%) (mean age: 78 ± 9 years, 42% female, 55% with secondary mitral regurgitation) were frail at baseline, which significantly decreased to 74 patients (28.7 %) at follow-up (P < 0.001). The frequency of frailty domains slowness, exhaustion, and inactivity significantly decreased, whereas weakness remained unchanged. Baseline frailty was significantly associated with comorbidities, N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels, and functional capacity, whereas frailty after PMVR was not associated with NT-proBNP levels. Predictors of postprocedural reversibility of frailty were NYHA functional class 

Comparison of vessel fractional flow reserve with invasive resting full-cycle ratio in patients with intermediate coronary lesions.

BACKGROUND: Vessel fractional flow reserve (vFFR) is a novel angiography-derived index for the assessment of myocardial ischemia without the need for pressure wires and hyperemic agents. vFFR has demonstrated very good diagnostic performance compared with the hyperemic index fractional flow reserve (FFR). The aim of this study was to compare vFFR to the non-hyperemic pressure ratio resting full-cycle ratio (RFR). METHODS: This was a retrospective, observational, single-center study of an all-comer cohort undergoing RFR assessment. Invasive coronary angiography was obtained without a dedicated vFFR acquisition protocol, and vFFR calculation was attempted in all vessels interrogated by RFR (1483 lesions of 1030 patients). RESULTS: vFFR could be analyzed in 986 lesions from 705 patients. Median diameter stenosis was 37% (interquartile range (IQR): 30.0-44.0%), vFFR 0.86 (IQR: 0.81-0.91) and RFR 0.94 (IQR: (0.90-0.97). The correlation between vFFR and RFR was strong (r = 0.70, 95% confidence interval (CI): 0.66-0.74, p < 0.001). Using RFR ≤0.89 as reference, the sensitivity, specificity, positive predictive value, negative predictive value, and overall diagnostic accuracy for vFFR were 77%, 93%, 77%, and 92% and 89%. vFFR yielded a high area under the curve (AUC) of 0.92 (95% CI: 0.90-0.94). The good diagnostic performance of vFFR was confirmed among subgroups of patients with diabetes, severe aortic stenosis, female gender and lesions located in the left anterior descending artery. CONCLUSION: vFFR has a high diagnostic performance taking RFR as the reference standard for evaluating the functional significance of coronary stenoses.

Early in-hospital discontinuation of aspirin on the first post-procedural day after percutaneous coronary stent implantation in patients on direct oral anticoagulation.

Background: Previous trials investigating antithrombotic therapy with a direct oral anticoagulant (DOAC) and a P2Y12 inhibitor after percutaneous coronary intervention (PCI), termed dual therapy, allowed a short period of triple therapy including a DOAC, a P2Y12 inhibitor, and aspirin. Aims: This study aimed to determine whether discontinuation of aspirin on the first post-procedural day is safe or causes ischemic events. Methods: Ischemic and bleeding events during hospitalization were investigated retrospectively in all patients treated with dual therapy (DOAC + P2Y12 inhibitor, designated as group 1) or triple therapy (DOAC + P2Y12 inhibitor+aspirin, designated as group 2) from day 1 after PCI at our center. Results: Of 4,564 consecutive PCI procedures, 1,059 (23.2%) had an indication for OAC. Of these, 322 met the inclusion criteria for group 1 and 62 for group 2. Baseline characteristics, CHA2DS2-VASc and HAS-BLED scores showed no relevant differences between the two groups, and the main indication for DOAC therapy was atrial fibrillation in both groups. Approximately » of patients were treated for acute coronary syndrome. The mean length of post-procedural hospitalization was 2.1 ± 2.5 and 2.2 ± 3.0 days in group 1 and 2, respectively (p = 0.305). One patient per group suffered a TIA (p = 0.297). There were no other ischemic events and no statistically significant differences in bleeding events. A subgroup analysis of cases hospitalized for ≥2 post-procedural days (group 1: 100 cases, mean 4.4 ± 3.4 days vs. group 2: 25 cases, mean 4.0 ± 4.1 days) confirmed these results. Conclusion: The initiation of dual therapy and thus discontinuation of aspirin on the first postprocedural day appears to be safe with respect to short-term ischemic events in a real-world population. Almost » of patients undergoing PCI have an indication for OAC, highlighting the relevance of this issue.

Prognostic impact of resting full-cycle ratio and diastolic non-hyperemic pressure ratios in patients with deferred revascularization.

BACKGROUND: Non-hyperemic pressure ratios (NHPRs) like resting full-cycle ratio (RFR), diastolic pressure ratio during entire diastole (dPR[entire]) and diastolic pressure ratio during wave-free period (dPR[WFP]) are increasingly used to guide revascularization. The effect of NHPRs on mid-term prognosis has not been well established. OBJECTIVE: We investigated the prognostic implications of NHRPs in patients whose revascularization was deferred based on fractional flow reserve (FFR) in a single-centre population. METHODS: NHPRs and FFR were calculated offline from pressure tracings by an independent core laboratory. Follow-up data were acquired through records of hospital visits or telephone interviews. The primary outcome was a vessel-oriented composite outcome (VOCO) (a composite of cardiac death, vessel-related myocardial infarction, and ischemia-driven revascularization) in deferred vessels at 2 years. RESULTS: 316 patients with 377 deferred lesions were analysed. Discordance of NHPRs and FFR was found in 13.0-18.3% of lesions. The correlation coefficient between NHPRs was 0.99 (95% confidence interval 0.99-1.00). At 2 years, VOCO occurred in 19 lesions (5.0%). Estimated glomerular filtration rate < 30 mL/min/1.73 m2 [hazard ratio (HR) 5.7, p = 0.002], previous myocardial infarction (HR 3.3, p = 0.018), diabetes (HR 2.7, p = 0.042), RFR ≤ 0.89 (HR 2.7, p = 0.041) and dPR[WFP] ≤ 0.89 (HR 2.7, p = 0.049) were associated with higher incidence of VOCO at 2 years in the univariable analysis. A non-significant trend was found for dPR[entire] (HR 1.9, p = 0.26). CONCLUSION: A positive RFR or dPR[WFP] were associated with a worse prognosis in deferred lesions, suggesting that the use of NHPRs in addition to FFR may improve risk estimation.

Contemporary treatment of mitral valve disease with transcatheter mitral valve implantation.

BACKGROUND: Transcatheter mitral valve implantation (TMVI) with self-expanding (SAV) or balloon-expandable (BAV) valves are rising as promising treatment options for high-risk patients with symptomatic mitral valve (MVD) disease unsuitable for alternative treatment options. AIMS: The aim of this study was to examine the clinical, procedural and outcome parameters of patients undergoing SAV or BAV for MVD. METHODS: In this observational and single-center case series, fifteen consecutive patients treated with the Tendyne Mitral Valve System (SAV) and thirty-one patients treated with SAPIEN prosthesis (BAV) were included. RESULTS: The patients (aged 78 years [interquartile range (IQR): 65.5 to 83.1 years], 41% women, EuroSCORE II 10.3% [IQR: 5.5 to 17.0%] were similar regarding baseline characteristics, despite a higher rate of prior heart valve surgery and prevalence of MV stenosis in the SAV-group. At discharge, the SAV-group had a mean transvalvular gradient of 4.2 mmHg, whereas the BAV-group had a mean transvalvular gradient of 6.2 mmHg. None or trace paravalvular leakage (PVL) was assessed in 85% in SAV-group and 80% in the BAV-group. 320 day all-cause and cardiac mortality rates were comparable in both groups (SAV: 26.7% vs BAV: 20%, p = 0.60). Four deaths occurred early in the SAV-group until 32 days of follow-up. CONCLUSIONS: In high-risk patients with MVD, TMVI presents a promising treatment option with encouraging mid-term outcomes and good valve durability. TMVI either with BAV or SAV may be developed to an established treatment option.

Alcohol-mediated renal denervation in patients with hypertension in the absence of antihypertensive medications.

BACKGROUND: Ultrasound and radiofrequency renal denervation (RDN) have been shown to safely lower blood pressure (BP) in hypertension. AIMS: The TARGET BP OFF-MED trial investigated the efficacy and safety of alcohol-mediated renal denervation (RDN) in the absence of antihypertensive medications. METHODS: This randomised, blinded, sham-controlled trial was conducted in 25 centres in Europe and the USA. Patients with a 24-hour systolic BP of 135-170 mmHg, an office systolic BP 140-180 mmHg and diastolic BP ≥90 mmHg on 0-2 antihypertensive medications were enrolled. The primary efficacy endpoint was the change in mean 24-hour systolic BP at 8 weeks. Safety endpoints included major adverse events up to 30 days. RESULTS: A total of 106 patients were randomised; the baseline mean office BP following medication washout was 159.4/100.4±10.9/7.0 mmHg (RDN) and 160.1/98.3±11.0/6.1 mmHg (sham), respectively. At 8 weeks post-procedure, the mean (±standard deviation) 24-hour systolic BP change was â2.9±7.4 mmHg (p=0.009) versus â1.4±8.6 mmHg (p=0.25) in the RDN and sham groups, respectively (mean between-group difference: 1.5 mmHg; p=0.27). There were no differences in safety events between groups. After 12 months of blinded follow-up, with medication escalation, patients achieved similar office systolic BP (RDN: 147.9±18.5 mmHg; sham: 147.8±15.1 mmHg; p=0.68) with a significantly lower medication burden in the RDN group (mean daily defined dose: 1.5±1.5 vs 2.3±1.7; p=0.017). CONCLUSIONS: In this trial, alcohol-mediated RDN was delivered safely but was not associated with significant BP differences between groups. Medication burden was lower in the RDN group up to 12 months.

Time-course of the electrophysiological maturation and integration of transplanted cardiomyocytes.

Electrophysiological maturation and integration of transplanted cardiomyocytes are essential to enhance safety and efficiency of cell replacement therapy. Yet, little is known about these important processes. The aim of our study was to perform a detailed analysis of electrophysiological maturation and integration of transplanted cardiomyocytes. Fetal cardiomyocytes expressing enhanced green fluorescent protein were transplanted into cryoinjured mouse hearts. At 6, 9 and 12 days after transplantation, viable slices of recipient hearts were prepared and action potentials of transplanted and host cardiomyocytes within the slices were recorded by microelectrodes. In transplanted cells embedded in healthy host myocardium, action potential duration at 50% repolarization (APD50) decreased from 32.2 ± 3.3 ms at day 6 to 27.9 ± 2.6 ms at day 9 and 19.6 ± 1.6 ms at day 12. The latter value matched the APD50 of host cells (20.5 ± 3.2 ms, P=0.78). Integration improved in the course of time: 26% of cells at day 6 and 53% at day 12 revealed no conduction blocks up to a stimulation frequency of 10 Hz. APD50 was inversely correlated to the quality of electrical integration. In transplanted cells embedded into the cryoinjury, which showed no electrical integration, APD50 was 49.2 ± 4.3 ms at day 12. Fetal cardiomyocytes transplanted into healthy myocardium integrate electrically and mature after transplantation, their action potential properties after 12 days are comparable to those of host cardiomyocytes. Quality of electrical integration improves over time, but conduction blocks still occur at day 12 after transplantation. The pace of maturation correlates with the quality of electrical integration. Transplanted cells embedded in cryoinjured tissue still possess immature electrophysiological properties after 12 days.

Spironolactone prevents aldosterone induced increased duration of atrial fibrillation in rat.

BACKGROUND: Atrial fibrillation (AF) is the most common sustained arrhythmia in clinical practice. The Renin-Angiotensin-Aldosterone-System plays a major role for the atrial structural and electrical remodelling. Recently elevated aldosterone levels have been suggested to increase the risk for the development of AF. METHODS: Rats were treated with aldosterone by means of an osmotic minipump (0.5µg/h) over a period of 4 weeks. AF was induced by transesophageal burst pacing. Action potentials (AP) were recorded from left atrial preparations with microelectrodes. Atrial collagen was quantified by histological studies. RESULTS: Aldosterone treatment resulted in hypertrophy as indicated by an increased ratio of heart weight/tibia length and doubled the time until the AF converted spontaneously into sinus rhythm (85.8±13.4 s vs. 38.3±6.9 s, p<0.01). This was associated with a significant shortening of the AP (APD90 26.2±1.1 vs. 31.2±1.9, p<0.05) and an increased protein expression of Kir2.1 and Kv1.5. Atrial collagen deposition was significantly greater in aldosterone-treated rats. The alterations could be prevented by additional application spironolactone. CONCLUSIONS: The results of the present study suggest that in addition to the structural remodelling aldosterone also promotes AF by altering repolarising potassium currents leading to action potential shortening.

The Hypertension Paradox: Survival Benefit After ST-Elevation Myocardial Infarction in Patients With History of Hypertension. A Prospective Cohort- and Risk-Analysis.

Background: Mortality after ST-elevation myocardial infarction (STEMI) is dependent from best-medical treatment after initial event. Objectives: Determining the impact of prescription of guideline-recommended therapy after STEMI in two cohorts, patients with and without history of arterial hypertension, on survival. Methods: 1,025 patients of the Cologne Infarction Model registry with invasively adjudicated STEMI were dichotomized according to their history of arterial hypertension. We recorded prescription rates and dosing of RAS-inhibitors, ß-blockers and statins in all patients. The primary outcome was all-cause death. Mean follow-up was 2.5 years. Results: Mean age was 64 ± 13 years, 246 (25%) were women. 749 (76%) patients had a history of hypertension. All-cause mortality was 24.2%, 30-day and 1-year mortality was 11.3% and 16.6%, respectively. History of hypertension correlated with lower mortality (hazard ratio [HR], @30 days: 0.41 [0.27-0.62], @1 year: 0.37 [0.26-0.53]). After adjusting for age, sex, Killip-class, diabetes mellitus, body-mass index, kidney function and statin prescription at discharge 1-year mortality HR was 0.24 (0.12-0.48). At discharge, prescription rates for RAS-inhibitors, ß-blockers and statins, as well as individual dosing and long-term persistence of RAS-inhibitors were higher in patients with history of hypertension. On the same lines, prescription rates for RAS-inhibitors, ß-blockers and statins at discharge correlated significantly with lower mortality regardless of history of hypertension. Conclusion: Patients with history of hypertension show higher penetration of guideline recommended drug therapy after STEMI, which may contribute to better survival. Better tolerance of ß-blockers and RAS-inhibitors in patients with history of hypertension, not hypertension itself, likely explains these differences in prescription and dosing.