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Dive into the research topics where Georg M. Fröhlich is active.

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Featured researches published by Georg M. Fröhlich.


European Heart Journal | 2010

Upgrading to resynchronization therapy after chronic right ventricular pacing improves left ventricular remodelling

Georg M. Fröhlich; Jan Steffel; David Hürlimann; Frank Enseleit; Thomas F. Lüscher; Frank Ruschitzka; William T. Abraham; Johannes Holzmeister

AIMS Chronic right ventricular (RV) pacing may impose ventricular dyssynchrony leading to LV remodelling and is associated with increased morbidity and mortality. Upgrading patients with chronic RV pacing to cardiac resynchronization therapy (CRT) may be considered to restore synchronicity and prevent these deleterious effects. METHODS AND RESULTS A total of 172 patients from two tertiary centres were analysed over a mean follow-up of 21.7 and 23.5 months after primary CRT implantation (n = 102) and CRT upgrade (n = 70), respectively. In the latter group, mean duration of RV pacing before CRT upgrade was 80.3 months, and ventricular stimulation was >95%. A significant improvement in left ventricular (LV) ejection fraction (10 and 11% absolute increase in primary CRT vs. upgrades, respectively), LV end-diastolic diameter index (-0.15 cm/m(2) vs. -0.2 cm/m(2)), and LV end-systolic diameter (-6.0 vs. -7.0 mm) was observed in both groups, which did not differ between primary CRT recipients and CRT upgrades. Response to CRT upgrade was independent of the underlying rhythm, QRS duration, duration of prior RV pacing, or LV function and size at baseline. Of note, even seven of nine patients with RV pacing >12 years responded favourably to CRT. CONCLUSION The current study demonstrates that CRT reverses LV remodelling in heart failure patients with chronic RV pacing in a similar way as in primary CRT recipients, even after very long periods of RV pacing. Our data, therefore, may have important implications for the treatment of pacemaker-dependent patients with heart failure, and support the use of CRT in this setting.


Circulation | 2012

Statins and the Risk of Cancer After Heart Transplantation

Georg M. Fröhlich; Kaspar Rufibach; Frank Enseleit; Mathias Wolfrum; Michelle von Babo; Michelle Frank; Reto Berli; Mathias Hermann; Johannes Holzmeister; Markus J. Wilhelm; Volkmar Falk; Georg Noll; Thomas F. Lüscher; Frank Ruschitzka

Background— Although newer immunosuppressive agents, such as mTOR (mammalian target of rapamycin) inhibitors, have lowered the occurrence of malignancies after transplantation, cancer is still a leading cause of death late after heart transplantation. Statins may have an impact on clinical outcomes beyond their lipid-lowering effects. The aim of the present study was to delineate whether statin therapy has an impact on cancer risk and total mortality after heart transplantation. Methods and Results— A total of 255 patients who underwent heart transplantation at the University Hospital Zurich between 1985 and 2007 and survived the first year were included in the present study. The primary outcome measure was the occurrence of any malignancy; the secondary end point was overall survival. During follow-up, a malignancy was diagnosed in 108 patients (42%). The cumulative incidence of tumors 8 years after transplantation was reduced in patients receiving a statin (34% versus 13%; 95% confidence interval, 0.25–0.43 versus 0.07–0.18; P<0.003). Statin use was associated with improved cancer-free and overall survival (both P<0.0001). A Cox regression model that analyzed the time to tumor formation with or without statin therapy, adjusted for age, male sex, type of cardiomyopathy, and immunosuppressive therapy (including switch to mTOR inhibitors or tacrolimus), demonstrated a superior survival in the statin group. Statins reduced the hazard of occurrence of any malignancy by 67% (hazard ratio, 0.33; 95% confidence interval, 0.21–0.51; P<0.0001). Conclusions— Although it is not possible to adjust for all potential confounders because of the very long follow-up period, this registry suggests that statin use is associated with improved cancer-free and overall survival after cardiac transplantation. These data will need to be confirmed in a prospective trial.


European Heart Journal | 2012

Effects of Pycnogenol on endothelial function in patients with stable coronary artery disease: a double-blind, randomized, placebo-controlled, cross-over study

Frank Enseleit; Isabella Sudano; Daniel Périat; Stephan Winnik; Mathias Wolfrum; Andreas J. Flammer; Georg M. Fröhlich; Priska Kaiser; Astrid Hirt; Sarah R. Haile; Nazmi Krasniqi; Christian M. Matter; Klaus Uhlenhut; Petra Högger; Thomas F. Lüscher; Frank Ruschitzka; Georg Noll

AIMS Extracts from pine tree bark containing a variety of flavonoids have been used in traditional medicine. Pycnogenol is a proprietary bark extract of the French maritime pine tree (Pinus pinaster ssp. atlantica) that exerts antioxidative, anti-inflammatory, and anti-platelet effects. However, the effects of Pycnogenol on endothelial dysfunction, a precursor of atherosclerosis and cardiovascular events, remain still elusive. METHODS AND RESULTS Twenty-three patients with coronary artery disease (CAD) completed this randomized, double-blind, placebo-controlled cross-over study. Patients received Pycnogenol (200 mg/day) for 8 weeks followed by placebo or vice versa on top of standard cardiovascular therapy. Between the two treatment periods, a 2-week washout period was scheduled. At baseline and after each treatment period, endothelial function, non-invasively assessed by flow-mediated dilatation (FMD) of the brachial artery using high-resolution ultrasound, biomarkers of oxidative stress and inflammation, platelet adhesion, and 24 h blood pressure monitoring were evaluated. In CAD patients, Pycnogenol treatment was associated with an improvement of FMD from 5.3 ± 2.6 to 7.0 ± 3.1 (P < 0.0001), while no change was observed with placebo (5.4 ± 2.4 to 4.7 ± 2.0; P = 0.051). This difference between study groups was significant [estimated treatment effect 2.75; 95% confidence interval (CI): 1.75, 3.75, P < 0.0001]. 15-F(2t)-Isoprostane, an index of oxidative stress, significantly decreased from 0.71 ± 0.09 to 0.66 ± 0.13 after Pycnogenol treatment, while no change was observed in the placebo group (mean difference 0.06 pg/mL with an associated 95% CI (0.01, 0.11), P = 0.012]. Inflammation markers, platelet adhesion, and blood pressure did not change after treatment with Pycnogenol or placebo. CONCLUSION This study provides the first evidence that the antioxidant Pycnogenol improves endothelial function in patients with CAD by reducing oxidative stress.


International Journal of Cardiology | 2012

Takotsubo cardiomyopathy has a unique cardiac biomarker profile: NT-proBNP/myoglobin and NT-proBNP/troponin T ratios for the differential diagnosis of acute coronary syndromes and stress induced cardiomyopathy

Georg M. Fröhlich; Boris Schoch; Florian Schmid; Philipp Keller; Isabella Sudano; Thomas F. Lüscher; Georg Noll; Frank Ruschitzka; Frank Enseleit

BACKGROUND Takotsubo cardiomyopathy (TC) usually is not recognized until heart catheterization reveals typical wall motion abnormalities in the absence of significant coronary artery disease. It was our aim to identify TC by its unique cardiac biomarker profile at an early stage and, preferably, with non-invasive procedures only. METHODS Ratios of N-terminal prohormone of brain natriuretic peptide (NT-proBNP) and myoglobin, NT-proBNP and troponin T (TnT), NT-proBNP and creatinekinase-MB (CK-MB) were compared in patients with TC (n=39), patients with ST-elevation myocardial infarction (STEMI, n=48) and patients with non-ST-elevation myocardial infarction (NSTEMI, n=34). Biomarkers were recorded serially at admission and at the three consecutive days. Optimal cut-off values to distinguish TC from STEMI and NSTEMI were calculated with receiver operator characteristic (ROC) curves. RESULTS At admission a NT-proBNP (ng/l)/myoglobin (μg/l) ratio of 3.8, distinguished TC from STEMI (sensitivity: 89%, specificity: 90%), while a NT-proBNP (ng/l)/myoglobin (μg/l) ratio of 14 separated well between TC and NSTEMI (sensitivity: 65%, specificity: 90%). Best differentiation of TC and ACS was possible with the ratio of peak levels of NT-proBNP (ng/l)/TnT (μg/l). A cut-off value of NT-proBNP (ng/l)/TnT (μg/l) ratio of 2889, distinguished TC from STEMI (sensitivity: 91%, specificity: 95%), while a NT-proBNP (ng/l)/TnT (μg/l) ratio of 5000 separated well between TC and NSTEMI (sensitivity: 83%, specificity: 95%). CONCLUSIONS TC goes along with a singular cardiac biomarker profile, which might be useful to identify patients with TC among patients presenting with acute coronary syndromes (ACS).


Circulation-cardiovascular Imaging | 2016

Quantifying the Area at Risk in Reperfused ST-Segment–Elevation Myocardial Infarction Patients Using Hybrid Cardiac Positron Emission Tomography–Magnetic Resonance Imaging

Heerajnarain Bulluck; Steven K White; Georg M. Fröhlich; Steven G. Casson; Celia O’Meara; Ayla Newton; Jennifer M. Nicholas; Peter Weale; Simon Wan; Alex Sirker; James C. Moon; Derek M. Yellon; Ashley M. Groves; Leon Menezes; Derek J. Hausenloy

Background—Hybrid positron emission tomography and magnetic resonance allows the advantages of magnetic resonance in tissue characterizing the myocardium to be combined with the unique metabolic insights of positron emission tomography. We hypothesized that the area of reduced myocardial glucose uptake would closely match the area at risk delineated by T2 mapping in ST-segment–elevation myocardial infarction patients. Methods and Results—Hybrid positron emission tomography and magnetic resonance using 18F-fluorodeoxyglucose (FDG) for glucose uptake was performed in 21 ST-segment–elevation myocardial infarction patients at a median of 5 days. Follow-up scans were performed in a subset of patients 12 months later. The area of reduced FDG uptake was significantly larger than the infarct size quantified by late gadolinium enhancement (37.2±11.6% versus 22.3±11.7%; P<0.001) and closely matched the area at risk by T2 mapping (37.2±11.6% versus 36.3±12.2%; P=0.10, R=0.98, bias 0.9±4.4%). On the follow-up scans, the area of reduced FDG uptake was significantly smaller in size when compared with the acute scans (19.5 [6.3%–31.8%] versus 44.0 [21.3%–55.3%]; P=0.002) and closely correlated with the areas of late gadolinium enhancement (R 0.98) with a small bias of 2.0±5.6%. An FDG uptake of ≥45% on the acute scans could predict viable myocardium on the follow-up scan. Both transmural extent of late gadolinium enhancement and FDG uptake on the acute scan performed equally well to predict segmental wall motion recovery. Conclusions—Hybrid positron emission tomography and magnetic resonance in the reperfused ST-segment–elevation myocardial infarction patients showed reduced myocardial glucose uptake within the area at risk and closely matched the area at risk delineated by T2 mapping. FDG uptake, as well as transmural extent of late gadolinium enhancement, acutely can identify viable myocardial segments.Background Hybrid Positron Emission Tomography and Magnetic Resonance (PET-MR) allows the advantages of MR in tissue characterizing the myocardium to be combined with the unique metabolic insights of PET. We hypothesized that the area of reduced myocardial glucose uptake would closely match the area-at-risk (AAR) delineated by T2-mapping in ST-segment elevation myocardial infarction (STEMI) patients.


Heart | 2013

Prophylactic implantable cardioverter defibrillator treatment in patients with end-stage heart failure awaiting heart transplantation

Georg M. Fröhlich; Johannes Holzmeister; Michael Hübler; Samira Hübler; Mathias Wolfrum; Frank Enseleit; Burkhardt Seifert; David Hürlimann; Hans B. Lehmkuhl; Georg Noll; Jan Steffel; Volkmar Falk; Thomas F. Lüscher; Roland Hetzer; Frank Ruschitzka

Objectives This study was designed to delineate the role of implantable cardioverter defibrillator (ICD) therapy for the primary and secondary prevention of sudden cardiac death in patients listed for heart transplantation. Setting Retrospective observational multicentre study. Patients 1089 consecutive patients listed for heart transplantation in two tertiary heart transplant centres were enrolled. Of 550 patients (51%) on the transplant list with an ICD, 216 had received their ICD for the primary prevention of sudden cardiac death and 334 for secondary prevention. 539 patients did not receive an ICD. Intervention Treatment with or without an ICD was left to the discretion of the heart failure specialist. Main outcome measure All-cause mortality. Results ICDs appear to be associated with a reduction in all-cause mortality in patients implanted with the device for primary and secondary prevention compared to those without an ICD despite a median time on the waiting list of only 8 months (estimated 1-year: 88±3% vs 77±3% vs 67±3%; p=0.0001). A Cox regressional hazard model (corrected for age, sex, underlying heart disease, atrial fibrillation, cardiac resynchronisation therapy, New York Heart Association (NYHA) class, ejection fraction, co-medication and year of listing) suggested an independent beneficial effect of ICDs that was most pronounced in patients who had received an ICD for primary prevention (HR 0.4, 95% CI 0.19 to 0.85; p=0.016). Conclusions ICD implantation appears to be associated with an immediate and sustained survival benefit for patients awaiting heart transplantation.


Pharmacology & Therapeutics | 2014

The cardioprotective effects of mineralocorticoid receptor antagonists

T.N.A. van den Berg; Gerard A. Rongen; Georg M. Fröhlich; Jaap Deinum; Derek J. Hausenloy; Niels P. Riksen

Despite state-of-the-art reperfusion therapy, morbidity and mortality remain significant in patients with an acute myocardial infarction. Therefore, novel strategies to limit myocardial ischemia-reperfusion injury are urgently needed. Mineralocorticoid receptor (MR) antagonists are attractive candidates for this purpose, since several clinical trials in patients with heart failure have reported a survival benefit with MR antagonist treatment. MRs are expressed by several cells of the cardiovascular system, including cardiomyocytes, cardiac fibroblasts, vascular smooth muscle cells, and endothelial cells. Experiments in animal models of myocardial infarction have demonstrated that acute administration of MR antagonists, either before ischemia or immediately at the moment of coronary reperfusion, limits infarct size. This action appears to be independent of the presence of aldosterone and cortisol, which are the endogenous ligands for the MR. The cardioprotective effect is mediated by a nongenomic intracellular signaling pathway, including adenosine receptor stimulation, and activation of several components of the Reperfusion Injury Salvage Kinase (RISK) pathway. In addition to limiting infarct size, MR antagonists can improve scar healing when administered shortly after reperfusion and can reduce cardiac remodeling post myocardial infarction. Clinical trials are currently being performed studying whether early administration of MR antagonists can indeed improve prognosis in patients with an acute myocardial infarction, independent of the presence of heart failure.


European Heart Journal | 2013

Haemodynamically irrelevant pericardial effusion is associated with increased mortality in patients with chronic heart failure

Georg M. Fröhlich; Philipp Keller; Florian Schmid; Mathias Wolfrum; Martin Osranek; Christian Falk; Georg Noll; Frank Enseleit; Markus Reinthaler; Pascal Meier; Thomas F. Lüscher; Frank Ruschitzka; Felix C. Tanner

AIMS Pericardial effusion (PE) is a common finding in cardiac patients with chronic heart failure. The prognostic relevance of a small, haemodynamically non-compromising PE in such patients, however, remains to be determined. METHODS AND RESULTS All patients referred to our heart failure clinic and having a baseline echocardiography and follow-up clinical visits were included. Patients with a haemodynamically relevant PE, acute myo-/pericarditis, systemic sclerosis, rheumatoid arthritis, heart transplantation, heart surgery within the last 6 months or malignancies within the last 3 years were excluded. Patients with or without a haemodynamically irrelevant PE were compared regarding all-cause mortality as the primary and cardiovascular death or need for heart transplantation as secondary outcomes. A total of 897 patients (824 patients in the control vs. 73 patients in the PE group) were included. In the PE group, left ventricular ejection fraction (LVEF) was lower [31%, interquartile range (IQR): 18.0-45.0] than in controls (34%, IQR: 25.0-47.0; P = 0.04), while the end-systolic diameters of the left ventricle and the left atrium were larger (P = 0.01 and P = 0.001, respectively). Similarly, in patients with PE, the right ventricle (RV) systolic function was lower (P < 0.005 for both the fractional area change and the tricuspid annulus movement), the dimensions of RV and right atrium (RA) were larger (P < 0.05 for RV and P < 0.01 for RA), and the degree of tricuspid regurgitation was higher (P < 0.0001). Furthermore, in the PE group, the heart rate was higher (P < 0.001) and the leukocyte count as well as CRP values were increased (P = 0.004 and P < 0.0001, respectively); beta-blocker use was less frequent (P = 0.04), while spironolactone use was more frequent (P = 0.03). The overall survival was reduced in the PE group compared with controls (P = 0.02). Patients with PE were more likely to suffer cardiovascular death (1-year estimated event-free survival: 86 ± 5 vs. 95 ± 1%; P = 0.01) and to require heart transplantation (1-year estimated event-free survival: 88 ± 4 vs. 95 ± 1%; P = 0.009). A multivariate Cox proportional hazard model revealed the following independent predictors of mortality: (a) PE (P = 0.04, hazard ratio (HR): 1.95, 95% confidence interval (CI): 1.0-3.7), (b) age (P = 0.04, HR: 1.02, 95% CI: 1.0-1.04) and (c) LVEF <35% (P = 0.03, HR: 1.7, 95% CI: 1.1-2.8). CONCLUSION In chronic heart failure, even minor PEs are associated with an increased risk of all-cause mortality, cardiac death, and need for transplantation.


Circulation | 2005

Aortic Coarctation Visualized by 16-Row Detector Multislice Computed Tomography

Georg M. Fröhlich; Michael Pörner; Rainer Wessely

A 34-year-old man was admitted to the hospital for increased shortness of breath. He was diagnosed as having arterial hypertension at age 14; a screen for secondary arterial hypertension had not been performed. Blood pressure …


International Journal of Cardiology | 2016

Endothelial function and sympathetic nervous system activity in patients with Takotsubo syndrome

Matthias Naegele; Andreas J. Flammer; Frank Enseleit; Susanne Roas; Michelle Frank; Astrid Hirt; Priska Kaiser; S. Cantatore; Christian Templin; Georg M. Fröhlich; Michel Romanens; Thomas F. Lüscher; Frank Ruschitzka; Georg Noll; Isabella Sudano

BACKGROUND Takotsubo syndrome (TTS) is an acute cardiomyopathy associated with intense physical or emotional stress. The precise mechanisms of the disease remain unclear. The aim of this study was to study alterations in endothelial function, vascular compliance and structure and muscle sympathetic activity in the stable phase of the disease. METHODS In this prospective observational study, patients with TTS and controls matched for age, sex, cardiovascular risk factors and medications were recruited. Flow-mediated vasodilatation (FMD) as a measure of endothelial dysfunction was the primary endpoint. Secondary endpoints included measurements of arterial stiffness, carotid atherosclerosis, quality of life and laboratory parameters. In a subset of patients, muscle sympathetic activity was measured before and after stress tests. RESULTS The study included 22 TTS patients and 21 matched controls. A significant increase in endothelial dysfunction was seen in TTS compared to controls (FMD 3.4±2.4% vs. 4.8±1.9%, p=0.016). No significant differences in arterial stiffness, intima-media thickness, quality of life and laboratory markers including endothelin-1 were noted. TTS patients showed a reduced carotid total plaque area compared to controls (TPA 17.3±15.1 vs 24.7±12.8mm2, p=0.02). A trend of increased muscle sympathetic activity at rest was observed in TTS patients vs. controls (53.5±28.4 vs. 29.4±16.5 bursts/100 heart beats, p=0.09) with no significant differences in muscle sympathetic activity in response to stress. CONCLUSIONS Our findings underscore the importance of endothelial dysfunction in patients with TTS which may be involved in the pathophysiology of this syndrome. CLINICALTRIALS. GOV IDENTIFIER NCT01249599.

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Pascal Meier

University College London

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Steven K White

University College London

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