Telemedical cardiac risk assessment by implantable cardiac monitors in patients after myocardial infarction with autonomic dysfunction (SMART-MI-DZHK9): a prospective investigator-initiated, randomised, multicentre, open-label, diagnostic trial.

BACKGROUND: Cardiac autonomic dysfunction after myocardial infarction identifies patients at high risk despite only moderately reduced left ventricular ejection fraction. We aimed to show that telemedical monitoring with implantable cardiac monitors in these patients can improve early detection of subclinical but prognostically relevant arrhythmic events. METHODS: We did a prospective investigator-initiated, randomised, multicentre, open-label, diagnostic trial at 33 centres in Germany and Austria. Survivors of acute myocardial infarction with left ventricular ejection fraction of 36-50% had biosignal analysis for assessment of cardiac autonomic function. Patients with abnormal periodic repolarisation dynamics (≥5·75 deg2) or abnormal deceleration capacity (≤2·5 ms) were randomly assigned (1:1) to telemedical monitoring with implantable cardiac monitors or conventional follow-up. Primary endpoint was time to detection of serious arrhythmic events defined by atrial fibrillation 6 min or longer, atrioventricular block class IIb or higher and fast non-sustained (>187 beats per min; ≥40 beats) or sustained ventricular tachycardia or fibrillation. This study is registered with ClinicalTrials.gov, NCT02594488. FINDINGS: Between May 12, 2016, and July 20, 2020, 1305 individuals were screened and 400 patients at high risk were randomly assigned (median age 64 years [IQR 57-73]); left ventricular ejection fraction 45% [40-48]) to telemedical monitoring with implantable cardiac monitors (implantable cardiac monitor group; n=201) or conventional follow-up (control group; n=199). During median follow-up of 21 months, serious arrhythmic events were detected in 60 (30%) patients of the implantable cardiac monitor group and 12 (6%) patients of the control group (hazard ratio 6·33 [IQR 3·40-11·78]; p<0·001). An improved detection rate by implantable cardiac monitors was observed for all types of serious arrhythmic events: atrial fibrillation 6 min or longer (47 [23%] patients vs 11 [6%] patients; p<0·001), atrioventricular block class IIb or higher (14 [7%] vs 0; p<0·001) and ventricular tachycardia or ventricular fibrillation (nine [4%] patients vs two [1%] patients; p=0·054). INTERPRETATION: In patients at high risk after myocardial infarction and cardiac autonomic dysfunction but only moderately reduced left ventricular ejection fraction, telemedical monitoring with implantable cardiac monitors was highly effective in early detection of subclinical, prognostically relevant serious arrhythmic events. FUNDING: German Centre for Cardiovascular Research (DZHK) and Medtronic Bakken Research Center.

Impella versus extracorporal life support in cardiogenic shock: a propensity score adjusted analysis.

AIMS: The mortality in cardiogenic shock (CS) is high. The role of specific mechanical circulatory support (MCS) systems is unclear. We aimed to compare patients receiving Impella versus ECLS (extracorporal life support) with regard to baseline characteristics, feasibility, and outcomes in CS. METHODS AND RESULTS: This is a retrospective cohort study including CS patients over 18 years with a complete follow-up of the primary endpoint and available baseline lactate level, receiving haemodynamic support either by Impella 2.5 or ECLS from two European registries. The decision for device implementation was made at the discretion of the treating physician. The primary endpoint of this study was all-cause mortality at 30 days. A propensity score for the use of Impella was calculated, and multivariable logistic regression was used to obtain adjusted odds ratios (aOR). In total, 149 patients were included, receiving either Impella (n = 73) or ECLS (n = 76) for CS. The feasibility of device implantation was high (87%) and similar (aOR: 3.14; 95% CI: 0.18-56.50; P = 0.41) with both systems. The rates of vascular injuries (aOR: 0.95; 95% CI: 0.10-3.50; P = 0.56) and bleedings requiring transfusions (aOR: 0.44; 95% CI: 0.09-2.10; P = 0.29) were similar in ECLS patients and Impella patients. The use of Impella or ECLS was not associated with increased odds of mortality (aOR: 4.19; 95% CI: 0.53-33.25; P = 0.17), after correction for propensity score and baseline lactate level. Baseline lactate level was independently associated with increased odds of 30 day mortality (per mmol/L increase; OR: 1.29; 95% CI: 1.14-1.45; P < 0.001). CONCLUSIONS: In CS patients, the adjusted mortality rates of both ECLS and Impella were high and similar. The baseline lactate level was a potent predictor of mortality and could play a role in patient selection for therapy in future studies. In patients with profound CS, the type of device is likely to be less important compared with other parameters including non-cardiac and neurological factors.

Platelet apelin receptor expression is reduced in patients with acute myocardial infarction.

BACKGROUND: The G-protein-coupled apelin receptor and its apelin ligand are an emerging regulatory system of the vascular homeostasis. To date, the implications of the apelin/apelin receptor system in athero-thrombosis are not completely clarified yet. This study determines the expression of the apelin receptor on human platelets, the effect of different apelin isoforms on platelet aggregation and the potential role of the apelin/apelin receptor system in acute myocardial infarction. METHODS: We applied immunofluorescence staining, Western Blot analysis, aggregometry, and flow cytometry to elucidate the role of the apelin receptor in activated platelets. Furthermore, in an observational pilot study, we assessed platelet apelin recpetor expression and apelin-17 plasma levels in patients with acute myocardial infarction (AMI, n = 27). RESULTS: Immunofluorescence staining indicates that the apelin receptor is located at the cell membrane in resting platelets and diminishes upon activation with a selective thrombin receptor-activating peptide (AP1, 3 to 100 µM). Western Blot analyses of AP1-activated platelets and their supernatants suggest that the apelin receptor is not predominantly internalized but is released from activated platelets. The isoform apelin-17 attenuated AP-1-induced platelet activation in-vitro, presumably via a NO-dependent mechanism. Furthermore, platelet apelin receptor expression was significantly reduced in patients with AMI (n = 27) compared to age-matched controls (n = 14; p < 0.05) and inversely correlated with troponin I plasma levels (r = -0.46; p = 0.03). Besides that, circulating apelin-17 was significantly reduced in MI patients compared to the control group. CONCLUSION: Taken together, our data support a crucial role of the platelet apelinergic system assuming an antithrombotic effect and therefore holding a potential diagnostic and therapeutic impact.

Impella Support for Acute Myocardial Infarction Complicated by Cardiogenic Shock.

BACKGROUND: Percutaneous mechanical circulatory support devices are increasingly used in acute myocardial infarction complicated by cardiogenic shock (AMI-CS), despite limited evidence for their effectiveness. The aim of this study was to evaluate outcomes associated with use of the Impella device compared with intra-aortic balloon pump (IABP) and medical treatment in patients with AMI-CS. METHODS: Data of patients with AMI-CS treated with the Impella device at European tertiary care hospitals were collected retrospectively. All patients underwent early revascularization and received optimal medical treatment. Using IABP-SHOCK II (Intraaortic Balloon Pump in Cardiogenic Shock II) trial inclusion and exclusion criteria, 372 patients were identified and included in this analysis. These patients were matched to 600 patients from the IABP-SHOCK II trial. The following baseline criteria were used as matching parameters: age, sex, mechanical ventilation, ejection fraction, prior cardiopulmonary resuscitation, and lactate. Primary end point was 30-day all-cause mortality. RESULTS: In total, 237 patients treated with an Impella could be matched to 237 patients from the IABP-SHOCK II trial. Baseline parameters were similarly distributed after matching. There was no significant difference in 30-day all-cause mortality (48.5% versus 46.4%, P=0.64). Severe or life-threatening bleeding (8.5% versus 3.0%, P<0.01) and peripheral vascular complications (9.8% versus 3.8%, P=0.01) occurred significantly more often in the Impella group. Limiting the analysis to IABP-treated patients as a control group did not change the results. CONCLUSIONS: In this retrospective analysis of patients with AMI-CS, the use of an Impella device was not associated with lower 30-day mortality compared with matched patients from the IABP-SHOCK II trial treated with an IABP or medical therapy. To further evaluate this, a large randomized trial is warranted to determine the effect of the Impella device on outcome in patients with AMI-CS. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT03313687.

The apelin receptor influences biomechanical and morphological properties of endothelial cells.

The adaption of endothelial cells to local flow conditions is a multifunctional process which leads to distinct alterations in cell shape, the subcellular distribution of structural proteins, and cellular function. G-protein-coupled receptors (GPCRs) have been identified to be fundamentally involved in such processes. Recently, we and others have shown that the expression of the endothelial GPCR apelin receptor (APJ) is regulated by fluid flow and that activation of APJ participates in signaling pathways which are related to processes of mechanotransduction. The present study aims to illuminate these findings by further visualization of APJ function. We show that APJ is located to the cellular junctions and might thus be associated with platelet endothelial cell adhesion molecule-1 (PECAM-1) in human umbilical vein endothelial cells (HUVEC). Furthermore, siRNA-mediated silencing of APJ expression influences the shear-induced adaption of HUVEC in terms of cytoskeletal remodeling, cellular elasticity, cellular motility, attachment, and distribution of adhesion complexes. Taken together, our results demonstrate that APJ is crucial for complemented endothelial adaption to local flow conditions.

Takayasu's arteritis: a case with relapse after urgent coronary revascularization.

BACKGROUND: Vasculitides are commonly unrecognized causes of coronary stenosis and myocardial ischemia. We report on a 24-year old patient with Takayasu's arteritis who underwent urgent percutaneous coronary intervention, suffered from symptomatic restenosis of the left main coronary artery during standard immunosuppressive therapy. CASE PRESENTATION: A 24-year old woman was referred for coronary angiography because of typical progressive angina pectoris. On bicycle ergometry, there were both reproducible symptoms and deep ST segment depressions on precordial leads. Semi-selective angiography of the left coronary artery revealed high-grade ostial stenosis. Because of persistent angina pectoris and electrocardiographic signs of acute myocardial ischemia, immediate percutaneous coronary angioplasty with subsequent implantation of an everolimus-eluting stent was performed. This intervention was performed with excellent angiographic results. Because of several concomitant criteria including hypoechogenicity on postprocedural intravascular ultrasonography, the diagnosis of Takayasu's disease was made. The patient was treated with prednisolone and cyclophosphamide for 5 months. Because of recurrent angina pectoris, another coronary angiography was performed, which revealed high-grade in-stent-restenosis. Immunomodulatory therapy was switched to high-dose prednisolone and the anti-IL-6 receptor antagonist tocilizumab. The high-grade in-stent-restenosis persisted, and aortocoronary bypass graft surgery was performed with two saphenous vein grafts to the left anterior descending and circumflex artery. Since then, the patient has been doing well for 2 years. CONCLUSION: In cases of treatment refractoriness during standard immunosuppressive therapy, more recently developed biological compounds may offer an alternative strategy.

Impact of atrial fibrillation detected by extended monitoring-A population-based cohort study.

BACKGROUND: The clinical relevance of extended monitoring of AF in the general population is unclear. The study evaluated the detection of AF using transtelephonic electrocardiography and the clinical relevance of additional AF findings, especially with regard to stroke risk and mortality. METHODS: The data of 1678 volunteers participating in the tele-ECG-subproject of the Study of Health in Pomerania was evaluated. Occurrence of AF as revealed by tele-ECG and conventional ECG was evaluated. Associations with mortality, history of stroke, and other clinical parameters were analyzed. RESULTS: AF was detected in 21 subjects (1.3%) by conventional ECG (ECG-AF) and in 43 (2.6%) by tele-ECG. All individuals with AF revealed by conventional ECG were also diagnosed to have AF by tele-ECG; 22 were diagnosed by tele-ECG only (Tele-AF). During follow-up (median: 6.3 years) 42/1635, 1/22, and 5/21 participants died in the no-AF-, tele-AF-, and ECG-AF groups (p < .001). Whereas, in comparison to the no-AF group, the risk of death was higher in the ECG-AF group (HR 9.4; 3.7-23.8; p < .001), there was no significant increase in mortality in the tele-AF group (HR 1.9; 0.26-14.0; p = .52). Prevalence of stroke history was higher in the ECG-AF group (19%; 5.5-42%) than with the no-AF (1.9%; 1.3-2.7%; p = .001) and the tele-AF groups (0%; 0-15%; p = .05). CONCLUSIONS: Tele-ECG identifies significantly more AF cases in a population-based setting compared to conventional ECG. The impact of AF diagnosed only by extended monitoring differs from conventionally diagnosed AF. Additional studies are warranted, since this might have an impact on clinical management.

Multicenter long-term validation of a minicourse in radiation-reducing techniques in the catheterization laboratory.

Patient radiation exposure in invasive cardiology is considerable. We aimed to investigate, in a multicenter field study, the long-term efficacy of an educational 90-minute workshop in cardiac invasive techniques with reduced irradiation. Before and at a median period of 2.5 months and 2.0 years after the minicourse (periods I, II, and III, respectively) at 5 German cardiac centers, 18 interventionalists documented various radiation parameters for 10 coronary angiographies. The median patient dose area product (DAP) for periods I, II, and III amounted to 26.6, 12.2, and 9.6 Gy × cm(2), respectively. The short-term and long-term effects were related to shorter median fluoroscopy times (180, 138, and 114 seconds), fewer radiographic frames (745, 553, and 417) because of fewer (11, 11, and 10) and shorter (64, 52, and 44 frames/run) runs, consistent collimation, and restriction to an adequate image quality; both radiographic DAP/frame (27.7, 17.3, and 18.4 mGy × cm(2)) and fluoroscopic DAP/second (26.6, 12.9, and 14.9 mGy × cm(2)) decreased significantly. Multivariate analysis over time indicated increasing efficacy of the minicourse itself (-55% and -64%) and minor influence of interventionist experience (-4% and -3% per 1,000 coronary angiographies, performed lifelong until the minicourse and until period III). In conclusion, autonomous self-surveillance of various dose parameters and feedback on individual radiation safety efforts supported the efficacy of a 90-minute course program toward long-lasting and ongoing patient dose reduction.

Efficacy of a minicourse in radiation-reducing techniques in invasive cardiology: a multicenter field study.

OBJECTIVES: Our goal was to validate an educational 90-min minicourse in lower-irradiating cardiac invasive techniques. BACKGROUND: Despite comprehensive radiation safety programs, patient radiation exposure in invasive cardiology remains considerable. METHODS: Before and at a median period of 3.7 months after the minicourse at 32 German cardiac centers, 177 interventionalists consistently documented radiation parameters for 10 coronary angiographies: dose area product (DAP), radiographic and fluoroscopic fractions, fluoroscopy time, and number of radiographic frames and runs. RESULTS: A total of 154 cardiologists attended the minicourse and achieved significant (p < 0.001) decrease in patients' median overall DAP (-48.4%), from baseline 26.5 to 13.7 Gy × cm(2). They reduced fluoroscopy times (-20.8%), radiographic runs (-9.1%), frames/run (-18.6%) and frames (-29.6%), and both radiographic DAP/frame (-27.4%) and fluoroscopic DAP/s (-39.3%), which indicate improved collimation, reduced-irradiation angulations, or adequate image quality. Dose-related parameters for the remaining 23 invited cardiologists unable to attend the workshop did not change significantly in univariate comparison. Multilevel analysis (p < 0.001) confirmed the efficacy of the minicourse itself (-14.7 Gy × cm(2)) and revealed higher DAP for increasing body mass index (+1.5 Gy × cm(2) per kg/m(2)), male sex (+5.8 Gy × cm(2)), age (+1.5 Gy × cm(2)/decade), and-owing to different settings during image acquisition-for advanced flat-panel detector systems (+9.0 Gy × cm(2)) versus older, traditional image intensifier systems. CONCLUSIONS: Despite significant required training in radiation safety for all interventional cardiologists, the presented additional 90-min minicourse significantly reduced patient dose.

Genetic Polymorphisms as Risk Stratification Tool in Primary Preventive ICD Therapy.

More and more implantable cardioverter-defibrillators (ICDs) are implanted as primary prevention of sudden cardiac death (SCD). However, major problem in practice is to identify high-risk patients for SCD. Different methods for noninvasive risk stratification do not have a sufficient positive or negative predictive value. Since current approaches lead to implantation of ICDs in a large number of patients who will never suffer an arrhythmic event and simultaneously patients still die of SCD who currently did not seem eligible for primary preventive ICD implantation, there is a need for additional tools for risk stratification. Epidemiological studies point to a hereditary risk of SCD. Different susceptibility of each person concerning arrhythmogenic events might be explained by genetic polymorphisms. By obtaining an individual "pattern" of polymorphisms of genes encoding for proteins which are important in arrhythmogenesis in one patient, risk stratification in primary prevention of SCD might by improved.

Asymptomatic sustained ventricular fibrillation in a patient with left ventricular assist device.

Optimal medical treatment, cardiac resynchronization, and the use of an implantable cardioverter defibrillator are established therapies of severe congestive heart failure. In refractory cases, left ventricular assist devices are more and more used not only as bridging to cardiac transplantation but also as destination therapy. Ventricular arrhythmias may represent a life-threatening condition and often result in clinical deterioration in patients with congestive heart failure. We report a case of asymptomatic sustained ventricular fibrillation with preserved hemodynamics caused by a nonpulsatile left ventricular assist device. Consecutive adequate but unsuccessful discharges of the implantable cardioverter defibrillator were the only sign of the usually fatal arrhythmia, prompting the patient to consult emergency services. Electrolyte supplementation and initiation of therapy with amiodarone followed by external defibrillation resulted in successful restoration of a stable cardiac rhythm after 3.5 hours.

Effect of verapamil on tachycardia-induced early cellular electrical remodeling in rabbit atrium.

We investigated the effects of a 7-day verapamil pretreatment (VPT, 7.5 mg/kg bodyweight subcutaneously every 12 h) on ionic currents and molecular mechanisms underlying tachycardia-induced early electrical remodeling after 24-h rapid atrial pacing (RAP, 600 bpm) in rabbit atrium. Animals were divided into four groups (n = 6 each group): control (not paced, no verapamil), paced only, verapamil only and verapamil and paced, respectively. VPT doubled ICa,L [7.0 +/- 0.7 pA/pF (control) vs 14.2 +/- 0.6 pA/pF (verapamil only)]. RAP reduced ICa,L by 48% to 3.6 +/- 0.7 pA/pF (paced only). RAP did not affect ICa,L in verapamil-treated animals and averaged 15.3 +/- 0.2 pA/pF (paced and verapamil). RAP resulted in a significant decrease of the expression of the alpha1c subunit (-24.7%) and the beta2A subunit (-13.3%), respectively. VPT led to a similar alteration of subunit expression as RAP ["control" vs "verapamil only", decrease of alpha1c subunit (-25.4%), but no significant change in beta2A subunit expression]. However, after VPT, further diminishment of alpha1c and beta2A subunit expression after rapid atrial pacing was absent. ("verapamil" vs "verapamil and paced", n = 6 both groups). RAP decreased Ito [-45%, 51.5 +/- 3.9 pA/pF (control) vs 26.8 +/- 1.5 pA/pF (paced only)] and was not influenceable by VPT. IK1 was neither affected by RAP nor verapamil pretreatment. Downregulation of alpha1c and beta2A subunit expression and the resulting decay of ICa,L current densities were prevented by verapamil. However, these effects are abolished by multiple other adverse effects of verapamil on atrial electrophysiology.