Autopsy after transcatheter aortic valve implantation.

Autopsy after transcatheter aortic valve implantation (TAVI) is a new field of interest in cardiovascular pathology. To identify the cause of death, it is important to be familiar with specific findings related to the time interval between the procedure and death. We aimed to provide an overview of the autopsy findings in patients with TAVI in their medical history divided by the timing of death with specific interest in the added value of autopsy over a solely clinically determined cause of death. In 8 European centres, 72 cases with autopsy reports were available. Autopsies were divided according to the time interval of death and reports were analysed. In 32 patients who died ≤72 h postprocedure, mortality resulted from cardiogenic or haemorrhagic shock in 62.5 and 34.4%, respectively. In 31 patients with mortality >72 h to ≤30 days, cardiogenic shock was the cause of death in 51.6% followed by sepsis (22.6%) and respiratory failure (9.7%). Of the nine patients with death >30 days, 88.9% died of sepsis, caused by infective endocarditis in half of them. At total of 12 patients revealed cerebrovascular complications. Autopsy revealed unexpected findings in 61.1% and resulted in a partly or completely different cause of death as was clinically determined. Autopsy on patients who underwent TAVI reveals specific patterns of cardiovascular pathology that clearly relate to the time interval between TAVI and death and significantly adds to the clinical diagnosis. Our data support the role of autopsy including investigation of the cerebrum in the quickly evolving era of cardiac device technology.

TINF2 Gene Mutation in a Patient with Pulmonary Fibrosis.

Pulmonary fibrosis is a frequent manifestation of telomere syndromes. Telomere gene mutations are found in up to 25% and 3% of patients with familial disease and sporadic disease, respectively. The telomere gene TINF2 encodes an eponymous protein that is part of the shelterin complex, a complex involved in telomere protection and maintenance. A TINF2 gene mutation was recently reported in a family with pulmonary fibrosis. We identified a heterozygous Ser245Tyr mutation in the TINF2 gene of previously healthy female patient that presented with progressive cough due to pulmonary fibrosis as well as panhypogammaglobulinemia at age 52. Retrospective multidisciplinary evaluation classified her as a case of possible idiopathic pulmonary fibrosis. Telomere length-measurement indicated normal telomere length in the peripheral blood compartment. This is the first report of a TINF2 mutation in a patient with sporadic pulmonary fibrosis, which represents another association between TINF2 mutations and this disease. Furthermore, this case underlines the importance of telomere dysfunction and not telomere length alone in telomere syndromes and draws attention to hypogammaglobulinemia as a manifestation of telomere syndromes.

Bicuspid stenotic aortic valves: clinical characteristics and morphological assessment using MRI and echocardiography.

BACKGROUND: Bicuspid aortic valve (BAV) is one of the most common congenital heart defects with a population prevalence of 0.5% to 1.3%. Identifying patients with BAV is clinically relevant because BAV is associated with aortic stenosis, endocarditis and ascending aorta pathology. METHODS AND RESULTS: Patients with severe aortic stenosis necessitating aortic valve replacement surgery were included in this study. All dissected aortic valves were stored in the biobank of the University Medical Centre Utrecht. Additionally to the morphological assessment of the aortic valve by the surgeon and pathologist, echocardiographic and magnetic resonance imaging (MRI) images were evaluated. A total of 80 patients were included of whom 32 (40%) were diagnosed with BAV by the surgeon (gold standard). Patients with BAV were significantly younger (55 vs 71 years) and were more frequently male. Notably, a significant difference was found between the surgeon and pathologist in determining valve morphology. MRI was performed in 33% of patients. MRI could assess valve morphology in 96% vs 73% with echocardiography. The sensitivity of MRI for BAV in a population of patients with severe aortic stenosis was higher than echocardiography (75% vs 55%), whereas specificity was better with the latter (91% vs 79%). Typically, the ascending aorta was larger in patients with BAV. CONCLUSION: Among unselected patients with severe aortic valve stenosis, a high percentage of patients with BAV were found. Imaging and assessment of the aortic valve morphology when stenotic is challenging.

T cells in cardiac allograft vasculopathy are skewed to memory Th-1 cells in the presence of a distinct Th-2 population.

Cardiac allograft vasculopathy (CAV) in heart transplantation (HTx) patients remains the major complication for long-term survival, due to concentric neointima hyperplasia induced by infiltrating mononuclear cells (MNC). Previously, we showed that activated memory T-helper-1 (Th-1) cells are the major component of infiltrating MNC in coronary arteries with CAV. In this study, a more detailed characterization of the MNC in human coronary arteries with CAV (n = 5) was performed and compared to coronary arteries without CAV (n = 5), by investigating MNC markers (CD1a, DRC-1, CD3, CD20, CD27, CD28, CD56, CD68, CD69, FOXP3 and HLA-DR), cytokines (IL-1A, 2, 4, 10, 12B, IFN-gamma, and TGF-beta1), and chemokine receptors (CCR3, CCR4, CCR5, CCR7, CCR8, CXCR3 and CX3CR1) by immunohistochemical double-labeling and quantitative PCR on mRNA isolated from laser microdissected layers of coronary arteries. T cells in the neointima and adventitia of CAV were skewed toward an activated memory Th-1 phenotype, but in the presence of a distinct Th-2 population. FOXP3 positive T cells were not detected and production of most cytokines was low or absent, except for IFN-gamma, and TGF-beta. This typical composition of T-helper cells and especially production of IFN-gamma and TGF-beta may play an important role in the proliferative CAV reaction.

TNFalpha in patients with end-stage heart failure on medical therapy or supported by a left ventricular assist device.

BACKGROUND: In the heart elevated levels of TNFalpha can cause lethal heart failure, like Dilated Cardiomyopathy (DCM). The level of TNFalpha production is in part determined by promoter gene polymorphisms. We investigated whether the TNFalpha promoter gene polymorphism is in this way involved in the outcome of end-stage heart failure and predicts whether patients require left ventricular assist device (LVAD) support or can be kept on medical therapy (MT)while awaiting heart transplantation (HTx). As most patients in this study received a heart transplant, the role of the TNFalpha polymorphisms in transplant rejection was studied as well. METHODS AND RESULTS: In twenty nine patients with DCM, 35 patients with Ischemic Heart Disease (IHD; both on MT), 26 patients on LVAD support and 61 cardiac transplant donors TNFalpha plasma level was detected by EASIA. In both patients groups high levels of TNFalpha plasma levels was observed however, in patients supported by LVAD this increase was much higher compared to patients on MT. Furthermore, this increase seems to be associated with the TNF 1 allele ('G' at position -308) instead of the TNF2 allele (A at position -308). The promoter polymorphisms at positions -238, -244 and -308 were observed by polymerase chain reaction and sequencing. Polymorphism at positions -238, -244 and -308 did not show any relevant differences between the groups. However, at position -308, a trend of a higher incidence of the TNF2 allele (an "A" at position -308) in DCM patients compared to donors was shown. The distribution of the TNF1 and TNF2 alleles was not different in patients on medical therapy compared to the patients supported by a LVAD. No association was found between patients' TNFalpha promoter gene polymorphism and rejection. However, patients that received a donor heart with the TNF2 allele developed more rejection episodes, compared to patients that received a donor heart with the TNF1 allele. CONCLUSION: TNFalpha levels are high in patients with end-stage heart failure on MT, but even higher in patients on LVAD support. These high TNFalpha plasma levels however, are not correlated with the TNF2 allele but seems to be associated with the TNF1 allele. Furthermore, in HTx the donor TNFalpha gene seem to play a more important role in severity of acute rejection than that of the patient.

Left ventricular pressure-volume relationships during normal growth and development in the adult rat--studies in 8- and 50-week-old male Wistar rats.

AIMS: Left ventricular (LV) pressure-volume relations provide relatively load-independent indexes of systolic and diastolic LV function, but few data are available on pressure-volume relations during growth and development in the normal adult heart. Furthermore, to quantify intrinsic ventricular function the indexes should be normalized for heart weight. However, in many studies the indexes are reported in absolute terms, or body weight-correction is used as a surrogate for heart weight-correction. METHODS: We determined pressure-volume relations in young (8-week-old, n = 13) and middle-aged (50-week-old, n = 19) male Wistar rats in relation to their heart and body weights. The animals were anaesthetized and a 2F pressure-conductance catheter was introduced into the LV to measure pressure-volume relations. RESULTS: Heart and body weights were significantly higher in the 50-week-old rats, whereas the heart-to-body weight ratio was significantly lower (2.74 +/- 0.32 vs. 4.41 +/- 0.37 mg g(-1), P < 0.001). Intrinsic systolic function, quantified by the slopes of the end-systolic pressure-volume relation (E(ES)), the dP/dt(MAX) vs. end-diastolic volume relation (S-dP), and the preload recruitable stroke work relation (PRSW), normalized for heart weight, was slightly decreased in the 50-week-old rats (S-dP: -6%, P < 0.004; PRSW: -3%, P < 0.06). Heart weight-corrected diastolic indexes were not significant different. The absolute indexes qualitatively showed the same results, but body-weight corrected pressure-volume indexes showed improved systolic function and significantly depressed diastolic function. CONCLUSIONS: Intrinsic systolic function slightly decreases from the juvenile to the middle-aged period in normal male Wistar rats. Furthermore, correction of pressure-volume indexes for body weight is not an adequate surrogate for heart weight-correction in these animals.

Remodeling by ventricular pacing in hypertrophying dog hearts.

OBJECTIVE: Asynchronous electrical activation of the left ventricle (LV), induced by ventricular pacing (VP), reduces mechanical load in early- and enhances it in late-activated regions. Consequently, chronic VP leads to asymmetric hypertrophy. We investigated whether such locally induced myocardial hypertrophy also occurs in the presence of pressure overload hypertrophy (POH). METHODS: POH was induced by aortic banding in puppies. At age 9 months, seven dogs were paced at the right ventricular (RV) apex at physiological heart rate for 6 months (POH-pace group), while four POH dogs served as POH-control group. Changes in volume of the LV cavity and the total LV wall and of five LV wall sectors were measured by means of 2D-echocardiography and X-ray marker detection. RESULTS: During the last 6 months of the protocol the volume of the five LV wall sectors increased in the POH-control group, ranging from 27+/-9 to 30+/-5% (mean+/-S.D.). In POH-pace animals sector wall volume in the four sectors at intermediate to long distance from the pacing site increased to a similar extent (ranging from 31+/-16 to 35+/-17%), but wall volume in the early-activated apical septum increased significantly less (17+/-21%). In these hearts myocyte diameter was significantly smaller in the apical septum than in the lateral LV wall. The regional difference in wall volume changes (19+/-21%) was significantly smaller in the POH-pace group than in chronically paced, non-hypertrophic, canine hearts in a previous study from our laboratory (43+/-14%). CONCLUSIONS: In hypertrophying hearts chronic pacing at the RV apex suppresses the development of hypertrophy in the early-activated apical septum but does not cause additional hypertrophy in late-activated regions, as is the case in non-hypertrophic hearts. The latter suggests that the local growth response is reduced in hypertrophying hearts.

Optimization of ventricular function by improving the activation sequence during ventricular pacing.

Abnormal electrical activation occurring during ventricular pacing reduces left ventricular (LV) pump function. Two strategies were compared to optimize LV function using ventricular pacing, minimal asynchrony and optimal sequence of electrical activation. ECG and hemodynamics aortic flowprobe, thermodilution cardiac output, LV pressure and its maximal rates of rise (LVdP/dtpos) and fall (LVdP/dtneg) were measured in anesthetized open-chest dogs (n = 7) with healthy hearts. The QRS duration (a measure of asynchrony of activation) was 47 +/- 5 ms during sinus rhythm and increased to 110 +/- 12 ms during DDD pacing at the right ventricular (RV) apex with a short AV interval. During pacing at the LV apex and LV base, the QRS duration was 8% +/- 7% and 15% +/- 7% (P < 0.05) longer than during RV apex pacing, respectively. Stroke volumes, LVdP/dtpos and LVdP/dtneg, however, were higher during LV apex (15% +/- 16%, 10% +/- 12% [P < 0.05], and 15% +/- 10%, respectively) and LV base pacing (11% +/- 12% [P < 0.05], 3% +/- 12%, and 3% +/- 11%, respectively) than during RV apex pacing. Systolic LV pressure was not influenced significantly by the site of pacing. Biventricular pacing (RV apex together with one or two LV sites) decreased the QRS duration by approximately 20% as compared with RV apex pacing, however, it did not improve stroke volumes, LVdP/dtpos and LVdP/dtneg beyond those during pacing at the LV apex alone. In conclusion, the sequence of electrical activation is a stronger determinant of ventricular function than the synchrony of activation. For optimal LV function the selection of an optimal single pacing site, like the LV apex, is more important than pacing from multiple sites.

Fluorescent microspheres are superior to radioactive microspheres in chronic blood flow measurements.

The accuracy of the fluorescent (FM) and radioactive microsphere (RM) techniques is similar in acute experiments but has not been established in chronic experiments. In the present study various combinations (at least pairs) of FM and/or RM labels were injected simultaneously between 2 mo and 5 min before each animal was killed. Blood flow was determined in many organs. Intramethod mean difference and variation did not change over time for FM but increased significantly for RM (from 1.8 +/- 1.4 to 25.6 +/- 21.8% and from 4.4 +/- 3.2 to 32.4 +/- 23.0% at 5 min and 2 mo, respectively). Also the FM-RM intermethod mean difference and variation increased (from -0.5 +/- 8.5 to 40.8 +/- 23.8% and from 23. 6 +/- 4.6 to 71.8 +/- 34.3%, respectively). After 2 mo, blood flow estimations were 20-50% lower with the various RM, whereas brain and liver blood flow values varied even more between isotopes. Underestimation started within 1 day for 51Cr and within 2 wk for 141Ce, 95Nb, and 85Sr. We conclude that FM are superior to RM for blood flow determination in experiments lasting longer than 1 day, presumably because of leaching of isotopes from RM.

Asynchronous electrical activation induces asymmetrical hypertrophy of the left ventricular wall.

BACKGROUND: Asynchronous electrical activation, induced by ventricular pacing, causes regional differences in workload, which is lower in early- than in late-activated regions. Because the myocardium usually adapts its mass and structure to altered workload, we investigated whether ventricular pacing leads to inhomogeneous hypertrophy and whether such adaptation, if any, affects global left ventricular (LV) pump function. METHODS AND RESULTS: Eight dogs were paced at physiological heart rate for 6 months (AV sequential, AV interval 25 ms, ventricular electrode at the base of the LV free wall). Five dogs were sham operated and served as controls. Ventricular pacing increased QRS duration from 47.2+/-10.6 to 113+/-16.5 ms acutely and to 133.8+/-25.2 ms after 6 months. Two-dimensional echocardiographic measurements showed that LV cavity and wall volume increased significantly by 27+/-15% and 15+/-17%, respectively. The early-activated LV free wall became significantly (17+/-17%) thinner, whereas the late-activated septum thickened significantly (23+/-12%). Calculated sector volume did not change in the LV free wall but increased significantly in the septum by 39+/-13%. In paced animals, cardiomyocyte diameter was significantly (18+/-7%) larger in septum than in LV free wall, whereas myocardial collagen fraction was unchanged in both areas. LV pressure-volume analysis showed that ventricular pacing reduced LV function to a similar extent after 15 minutes and 6 months of pacing. CONCLUSIONS: Asynchronous activation induces asymmetrical hypertrophy and LV dilatation. Cardiac pump function is not affected by the adaptational processes. These data indicate that local cardiac load regulates local cardiac mass of both myocytes and collagen.

Asymmetric thickness of the left ventricular wall resulting from asynchronous electric activation: a study in dogs with ventricular pacing and in patients with left bundle branch block.

Various kinds of abnormal, asynchronous electric activation of the left ventricle (LV) decrease mechanical load in early versus late activated regions of the ventricular wall. Because myocardium usually adapts its mass to changes in workload, we investigated by echocardiography whether regional differences in wall thickness are present in two kinds of asynchronous electric activation of different origin and conduction pathway: epicardial ventricular pacing in dogs and left bundle branch block (LBBB) in patients. In six dogs, 3 months of epicardial LV pacing at physiologic heart rates decreased the thickness of the early activated anterior wall by 20.5 +/- 8.1% without significantly changing LV cavity area and septal thickness. In a retrospective study of 228 LBBB patients, the early activated septum was significantly thinner than the late activated posterior wall. The asymmetry most pronounced was as large as 10% in 28 patients with LBBB and paradoxic septal motion. No difference in regional wall thickness was present in 154 control patients. In conclusion, chronic asynchronous electric activation in the heart induces redistribution of cardiac mass. This redistribution occurs in hearts, which differ in impulse conduction pathway, disease, and species and is characterized by thinning of early versus late activated myocardium.

Fluorescent microspheres to measure organ perfusion: validation of a simplified sample processing technique.

A disadvantage of nonradioactive microsphere techniques is that the processing of samples is time-consuming and complex. We developed and validated a simplified processing method for the fluorescent microsphere (FM) technique. In seven anesthetized dogs with coronary artery stenosis up to six different FM and five different radioactivity labeled microspheres (RM) were injected. Two FM and two RM labels were injected simultaneously to enable inter- and intramethod comparison. After gamma-counting samples of blood, myocardium (n = 168), and other organs (n = 59) were digested in test tubes with 2 N ethanolic KOH (60 degrees C, 48 h), microspheres were sedimented by centrifugation, dye was extracted in the same tube, and fluorescence was measured. With this processing method, recovery of FM was approximately 100%. Good correlations for inter- and intramethod comparisons were found [r = 0.985 +/- 0.01 (mean +/- SD)]. The lower intermethod correlation for blue microspheres (r = 0.958) indicates that the use of this label is less desirable. RM and FM endocardial-to-epicardial blood flow ratios correlated well (r = 0.974). With this one-vessel centrifugal sedimentation method and at least five fluorescently labeled microspheres, blood flow can be reliably measured in various organs, including ischemic myocardium.