Matthias Pauschinger

Utility of Doppler Echocardiography and Tissue Doppler Imaging in the Estimation of Diastolic Function in Heart Failure With Normal Ejection Fraction A Comparative Doppler-Conductance Catheterization Study

Background— Various conventional and tissue Doppler echocardiographic indexes were compared with pressure–volume loop analysis to assess their accuracy in detecting left ventricular (LV) diastolic dysfunction in patients with heart failure with normal ejection fraction (HFNEF). Methods and Results— Diastolic dysfunction was confirmed by pressure–volume loop analysis obtained by conductance catheter in 43 patients (19 men) with HFNEF. Their Doppler indexes were compared with those of 12 control patients without heart failure symptoms and with normal ejection fraction. Invasively measured indexes for diastolic relaxation (&tgr;, dP/dtmin), LV end-diastolic pressure, and LV end-diastolic pressure–volume relationship (stiffness, b [dP/dV], and stiffness constant, &bgr;) were correlated with several conventional mitral flow and tissue Doppler imaging indexes. Conventional Doppler indexes correlated moderately with the degree of LV relaxation index, &tgr; (E/A: r=−0.36, P=0.013; isovolumic relaxation time: r=0.31, P=0.040) and b (deceleration time: r=0.39, P=0.012) but not with &bgr;, in contrast to the tissue Doppler imaging indexes E’/A’lateral (r=−0.37, P=0.008) and E/E’lateral (r=0.53, P<0.001). Diastolic dysfunction was detected in 70% of the HFNEF patients by mitral flow Doppler but in 81% and 86% by E’/A’lateral, and E/E’lateral, respectively. Conclusions— Of all echocardiographic parameters investigated, the LV filling index E/E’lateral was identified as the best index to detect diastolic dysfunction in HFNEF in which the diagnosis of diastolic dysfunction was confirmed by conductance catheter analysis. We recommend its use as an essential tool for noninvasive diagnostics of diastolic function in patients with HFNEF.

Detection of viruses in myocardial tissues by polymerase chain reaction : evidence of adenovirus as a common cause of myocarditis in children and adults

OBJECTIVES The purpose of this study was to analyze cardiac tissue and blood for viral genomes using polymerase chain reaction (PCR) to define the common viral etiologies of myocarditis by age group. BACKGROUND Enteroviruses are considered the most common cause of myocarditis at all ages. Diagnosis relies on viral cultures, serology, and cardiac histology, which lack sensitivity, as well as PCR. However, in many cases enteroviruses are not detected. METHODS Cardiac samples were obtained for PCR analysis from patients with myocarditis (n = 624) and dilated cardiomyopathy (DCM) (n = 149). Patients were analyzed by age group, including neonates (n = 116), infants (n = 191), toddlers (n = 87), children (n = 110), adolescents (n = 92), and adults (n = 177). After nucleic acids had been extracted from an endomyocardial biopsy, an explant, or autopsy samples, PCR and reverse transcription PCR were performed to detect the genomic sequences of enterovirus, adenovirus, cytomegalovirus (CMV), herpes simplex virus (HSV), Epstein-Barr virus (EBV), parvovirus, respiratory syncytial virus (RSV), and influenza A virus. RESULTS Viral genome was amplified (adenovirus = 142, enterovirus = 85, CMV = 18, parvovirus = 6, influenza A = 5, HSV = 5, EBV = 3, RSV = 1) from 239 (38%) of the 624 samples from myocarditis patients, including 26 patient samples in which dual infection was found. Virus was detected in 30 (20%) of 149 DCM patient samples; only adenovirus (n = 18) and enterovirus (n = 12) were detected. CONCLUSIONS Polymerase chain reaction identified adenovirus as the most common virus in the myocardium of children and adults with myocarditis and DCM. Although enteroviruses are also found in these patients, they appear to be a less common cause of myocarditis than adenovirus.

Viral Persistence in the Myocardium Is Associated With Progressive Cardiac Dysfunction

Background—Cardiotropic viral infections have been suspected as one possible cause of myocarditis and dilated cardiomyopathy. Although adverse outcomes in dilated cardiomyopathy patients have been documented, the natural course of heart diseases caused by cardiotropic viruses is unknown. Methods and Results—Consecutive patients (n=172) with biopsy-proven viral infection in endomyocardial biopsies (EMBs) were followed up by reanalysis of EMBs and hemodynamic measurements after a median period of 6.8 months (range, 5.4 to 11.9). Nested polymerase chain reaction (PCR) and reverse transcription–PCR were performed to analyze the genomic sequences. Myocardial inflammation was assessed by histology and immunohistology. At baseline, 32.6% of EMBs in the study group contained enteroviral (EV) RNA, 8.1% adenovirus (ADV) DNA, 36.6% parvovirus B19 (PVB19) DNA, and 10.5% human herpesvirus type 6 (HHV6) DNA. In 12.2% of the samples, dual infection with PVB19 and HHV6 was present. Follow-up analysis of EMBs by PCR documented spontaneous clearance of viral genomes in 36.2% (55/151) of all patients with single infections. Virus-specific clearance rates were 50% for EV, 35.7% for ADV, 22.2% for PVB19, and 44.4% for HHV6. In patients with dual infection with PVB19+ and HHV6+-, HHV6 was cleared in 42.8% (9/21), whereas PVB19 persisted in all 21 patients. Clearance of viral genomes was associated with a significant improvement in left ventricular ejection fraction (LVEF), improving from 50.2±19.1% to 58.1±15.9% (P<0.001). In contrast, LV function decreased in patients with persisting viral genomes (LVEF, 54.3±16.1% versus 51.4±16.1%, P<0.01). Conclusions—In this first biopsy-based analysis of the course of viral heart disease, we show that EV, ADV, PVB19, and HHV6 persistence detected in the myocardium of patients with LV dysfunction was associated with a progressive impairment of LVEF, whereas spontaneous viral elimination was associated with a significant improvement in LV function.

Interferon-β Treatment Eliminates Cardiotropic Viruses and Improves Left Ventricular Function in Patients With Myocardial Persistence of Viral Genomes and Left Ventricular Dysfunction

Background—Viral infections are important causes of myocarditis and may induce cardiac dysfunction and finally lead to dilated cardiomyopathy. We investigated whether interferon (IFN)-&bgr; therapy is safe and may achieve virus clearance and prevent deterioration of left ventricular (LV) function in patients with myocardial virus persistence. Methods and Results—In this phase II study, 22 consecutive patients with persistence of LV dysfunction (history of symptoms, 44±27 months) and polymerase chain reaction–proven enteroviral or adenoviral genomes were treated with 18×106 IU/week IFN-&bgr; (Beneferon) subcutaneously for 24 weeks. Histological and immunohistological analysis of endomyocardial biopsies was used to characterize myocardial inflammation. LV diameters and ejection fraction were assessed by echocardiography and angiography, respectively. During the treatment period, IFN-&bgr; was well tolerated by all patients. No patient deteriorated. Clearance of viral genomes was observed in 22 of 22 of patients after antiviral therapy. Virus clearance was paralleled by a significant decrease of LV end diastolic and end systolic diameters, decreasing from 59.7±11.1 to 56.5±10.0 mm (P <0.001) and 43.2±13.6 to 39.4±12.1 mm (P <0.001), respectively. LV ejection fraction increased from 44.6±15.5% to 53.1±16.8% (P <0.001). Conclusions—A 6 months, IFN-&bgr; treatment was safe in patients with myocardial enteroviral or adenoviral persistence and LV dysfunction and resulted in elimination of viral genomes (22 of 22 patients) and improved LV function (15 of 22 patients).

Cardiac Troponin T in Patients With Clinically Suspected Myocarditis

OBJECTIVES The present study investigated whether myocyte injury can be assessed sensitively by measurement of serum levels of cardiac troponin T (cTnT) in patients with clinically suspected myocarditis and whether cTnT levels may predict the results of histologic and immunohistologic analysis of endomyocardial biopsy specimens. BACKGROUND Conventionally used laboratory variables often fail to show myocyte injury in patients with clinically suspected myocarditis, possibly because of a low extent of myocardial injury in these patients. Sensitive variables for myocyte injury have not yet been investigated. METHODS Eighty patients with clinically suspected myocarditis were screened for creatine kinase (CK) activity, MB isoform of CK (CK-MB) activity and cTnT. Endomyocardial biopsy specimens were examined histologically and immunohistologically. RESULTS cTnT was elevated in 28 of 80 patients with clinically suspected myocarditis, CK in 4 and CK-MB in 1. Histologic analysis alone of the endomyocardial biopsy specimen revealed evidence of myocarditis in only five patients, all with elevated cTnT levels. Twenty-three of 28 patients with elevated cTnT levels had histologically negative findings for myocarditis. Additional immunohistologic analysis revealed evidence of myocarditis in 26 (93%) of 28 patients with elevated cTnT levels and in 23 (44%) of 52 patients with normal cTnT levels. Mean cTnT levels were higher in patients with myocarditis proved histologically or immunohistologically, or both, than in patients without myocarditis (0.59 +/- 1.68 vs. 0.04 +/- 0.05, p < 0.001). CONCLUSIONS Measurement of serum levels of cTnT provides evidence of myocyte injury in patients with clinically suspected myocarditis more sensitively than does conventional determination of cardiac enzyme levels. Myocardial cell damage may be present even in the absence of histologic signs of myocarditis. Additional immunohistologic analysis often shows lymphocytic infiltrates in these patients. Elevated levels of cTnT are highly predictive for myocarditis in this group.

Expression of coxsackie adenovirus receptor and alphav-integrin does not correlate with adenovector targeting in vivo indicating anatomical vector barriers.

Recombinant adenoviral vectors are broadly applied in gene therapy protocols. However, adenovector-mediated gene transfer has limitations in vivo. One of these is the low gene transfer rate into organs other than the liver after systemic intravenous vector injection. Local direct injection into the target organ has been used as one possible solution, but increases necessary equipment and methodology and is traumatic to the target. Wild-type adenovirus infection as well as adenovector-mediated gene transfer depends on virus interaction with the Coxsackie adenovirus receptor (CAR) mediating virus attachment to the cell surface, and on interaction with αvβ3 and αvβ5 integrins mediating virus entry into the cell. In order to assess the receptor-associated potential of different tissues to act as adenovector targets, we have therefore determined CAR and αv-integrin expression in multiple organs from different species. In addition, we have newly determined several human, rat, pig and dog CAR-mRNA sequences. Sequence comparison and structural analyses of known and of newly determined sequences suggests a potential adenovirus binding site between amino acids 29 and 128 of the CAR. With respect to the virus receptor expression patterns we found that CAR-mRNA expression was extremely variable between different tissues, with the highest levels in the liver, whereas αv-integrin expression was far more homogenous among different organs. Both CAR and αv-integrin showed similar expression patterns among different species. There was no correlation, however, between the adenovector expression patterns after intravenous, intracardiac and aortic root injection, respectively, and the virus receptor patterns. In summary, many organs carry both receptors required to make them potential adenovector targets. In sharp contrast, their actual targeting clearly indicates that adenovirus receptor expression is necessary but not sufficient for vector transfer after systemic injection. The apparently very important role of anatomical barriers, in particular the endothelium, requires close attention when developing non-traumatic, organ-specific gene therapy protocols.

Role of Left Ventricular Stiffness in Heart Failure With Normal Ejection Fraction

Background— Increased left ventricular stiffness is a distinct finding in patients who have heart failure with normal ejection fraction (HFNEF). To elucidate how diastolic dysfunction contributes to heart failure symptomatology during exercise, we conducted a study using an invasive pressure-volume loop approach and measured cardiac function at rest and during atrial pacing and handgrip exercise. Methods and Results— Patients with HFNEF (n=70) and patients without heart failure symptoms (n=20) were enrolled. Pressure-volume loops were measured with a conductance catheter during basal conditions, handgrip exercise, and atrial pacing with 120 bpm to analyze diastolic and systolic left ventricular function. During transient preload reduction, the diastolic stiffness constant was measured directly. Diastolic function with increased stiffness was significantly impaired in patients with HFNEF during basal conditions. This was associated with increased end-diastolic pressures during handgrip exercise and with decreased stroke volume and a leftward shift of pressure-volume loops during atrial pacing. Conclusions— Increased left ventricular stiffness contributed to increased end-diastolic pressure during handgrip exercise and decreased stroke volume during atrial pacing in patients with HFNEF. These data suggest that left ventricular stiffness modulates cardiac function in HFNEF patients and suggests that diastolic dysfunction with increased stiffness is a target for treating HFNEF.

Dilated Cardiomyopathy Is Associated With Significant Changes in Collagen Type I/III ratio

BACKGROUND It is controversial whether myocardial fibrosis in end-stage dilated cardiomyopathy (DCM) is associated with altered collagen type I/type III (Col I/Col III) ratio. METHODS AND RESULTS Patients with DCM (ejection fraction [EF] <50%, n=12) and with mild global left ventricular dysfunction (EF >50%, n=18) were examined. Col I, Col III, and transforming growth factors-beta1 (TGF-beta1) and -beta2 (TGF-beta2) gene expression in endomyocardial biopsies was evaluated by quantitative competitive reverse transcriptase-polymerase chain reaction (qRT-PCR). Collagen content was quantified after picrosirius red and immunohistological staining and by hydroxyproline assay. In patients with EF <50%, there was a pronounced 2- to 6-fold increase of myocardial Col I mRNA abundance (P<0.01), with a corresponding 1.6-fold increase at the protein level versus that found in patients with EF >50%. The Col III mRNA abundance showed a 2.0-fold increase (P<0.04). There was a relevant shift in the Col I/Col III mRNA ratio for DCM patients (Col I/Col III, 8.2) compared with patients with an EF >50% (Col I/Col III, 6. 4). In addition, total collagen content was increased in patients with EF <50% (n=3) (4.3+/-0.1%) compared with patients with EF >50% (n=8) (2.7+/-0.9%) (P<0.004). The biochemically determined ratio of hydroxyproline/total protein (n=12) was correlated to the Col I mRNA abundance (P<0.05, r=0.77). TGF-beta1 and TGF-beta2 showed elevated myocardial mRNA abundances (1- to 7-fold and 4- to 5-fold, respectively) in DCM patients. CONCLUSIONS Differential increase of Col I and Col III leads to an increased Col I/Col III ratio in DCM myocardium. Because Col I provides substantial tensile strength and stiffness, this may contribute to systolic and in particular diastolic dysfunction in DCM.

Parvovirus B19 Infection Mimicking Acute Myocardial Infarction

Background—Enteroviruses (EVs) and adenoviruses (ADVs) have been considered common causes of myocarditis and dilated cardiomyopathy. In the present study, we report on the association of parvovirus B19 (PVB19) genomes in the clinical setting of acute myocarditis. Methods and Results—This study included 24 consecutive patients admitted to our hospital within 24 hours after onset of chest pain. Acute myocardial infarction had been excluded in all patients by coronary angiography. Endomyocardial biopsies were analyzed by nested polymerase chain reaction/reverse transcriptase-polymerase chain reaction for EV, ADV, PVB19, human cytomegalovirus, Epstein-Barr virus, Chlamydia pneumoniae, influenza virus A and B, and Borrelia burgdorferi genomes, respectively, followed by direct sequencing of the amplification products. All patients presented with acute onset of angina pectoris and ST-segment elevations or T-wave inversion mimicking acute myocardial infarction. Mean baseline peak creatinine kinase and creatine kinase-isoenzyme fraction were 342±241 U/L and 32±20 U/L, respectively. Mean troponin T was increased to 7.5±15.0 ng/mL and C-reactive protein to 91±98 mg/mL. Eighteen patients had global or regional wall motion abnormalities (ejection fraction 62.5±15.5%). Histological analysis excluded the presence of active or borderline myocarditis in all but one patient. PVB19, EV, and ADV genomes were detected in the myocardium of 12, 3, and 2 patients, respectively (71%). Follow-up biopsies of virus-positive patients (11 of 17) demonstrated persistence of PVB19 genomes in 6 of 6 patients, EV genomes in 2 of 3 patients, and ADV genomes in 1 of 2 patients, respectively. Conclusions—Virus genomes can be demonstrated in 71% of patients with normal coronary anatomy, clinically mimicking acute myocardial infarction. In addition to EVs and ADVs, PVB19 was the most frequent pathogen.

High Prevalence of Cardiac Parvovirus B19 Infection in Patients With Isolated Left Ventricular Diastolic Dysfunction

Background—The etiology of left ventricular (LV) isolated diastolic dysfunction often remains unclear. In the present study, we report a strong association between parvovirus B19 (PVB19) genomes and isolated LV diastolic dysfunction. Methods and Results—In 70 patients (mean±SD age, 43±11 years) admitted with exertional dyspnea and/or reduced exercise tolerance despite preserved LV systolic contractility (ejection fraction=68%), isolated diastolic dysfunction was clinically suspected. Patients with classic risk factors for diastolic dysfunction such as hypertension, coronary heart disease, diabetes mellitus, or pulmonary disease had been excluded. Diastolic function was assessed by echocardiography and LV and RV catheterization. Endomyocardial biopsies (EMBs) were analyzed for the presence of storage or infiltrative diseases or myocarditis, including molecular screening for cardiotropic virus genomes. In a substudy of 24 patients who reported atypical angina, coronary endothelial function was additionally investigated with a coronary Doppler flow-wire technique. In 37 of 70 patients (53%), isolated diastolic dysfunction was confirmed as the cause of their clinical symptoms. No evidence for cardiac storage or infiltrative diseases was found in these cases, but in 35 of 37 of these patients (95%), cardiotropic virus genomes were detected in EMBs (P<0.001). PVB19 was the most frequent pathogen in 31 of 37 patients (84%). In a subgroup of 10 patients with diastolic dysfunction and coexisting endothelial dysfunction, all 10 (100%) were PVB19 positive. Conclusions—PVB19 genomes were predominant in patients with unexplained, isolated diastolic dysfunction. A strong association with the incidence of endothelial dysfunction was obvious, consistent with the hypothesis that PVB19-induced endothelial dysfunction may be a possible pathomechanism underlying diastolic dysfunction.