Doppler-derived intracoronary physiology indices predict the occurrence of microvascular injury and microvascular perfusion deficits after angiographically successful primary percutaneous coronary intervention.

Background: A total of 40% to 50% of patients with ST-segment-elevation myocardial infarction develop microvascular injury (MVI) despite angiographically successful primary percutaneous coronary intervention (PCI). We investigated whether hyperemic microvascular resistance (HMR) immediately after angiographically successful PCI predicts MVI at cardiovascular magnetic resonance and reduced myocardial blood flow at positron emission tomography (PET).

Methods And Results: Sixty patients with ST-segment-elevation myocardial infarction were included in this prospective study.

Prediction of long-term outcome of cardiac resynchronization therapy by acute pressure-volume loop measurements.

Aims: Invasive assessment of acute haemodynamic response to biventricular pacing has been proposed as a tool to determine individual response and to optimize the effects of CRT. However, the long-term results of this approach have been poorly studied. The present study relates acute haemodynamic effects of CRT to long-term outcome.

Low myocardial protein kinase G activity in heart failure with preserved ejection fraction.

Background: Prominent features of myocardial remodeling in heart failure with preserved ejection fraction (HFPEF) are high cardiomyocyte resting tension (F(passive)) and cardiomyocyte hypertrophy. In experimental models, both reacted favorably to raised protein kinase G (PKG) activity. The present study assessed myocardial PKG activity, its downstream effects on cardiomyocyte F(passive) and cardiomyocyte diameter, and its upstream control by cyclic guanosine monophosphate (cGMP), nitrosative/oxidative stress, and brain natriuretic peptide (BNP).

Improved clinical outcome after invasive management of patients with recent myocardial infarction and proven myocardial viability: primary results of a randomized controlled trial (VIAMI-trial).

Background: Patients with ST-elevation myocardial infarction (STEMI) not treated with primary or rescue percutaneous coronary intervention (PCI) are at risk for recurrent ischemia, especially when viability in the infarct-area is present. Therefore, an invasive strategy with PCI of the infarct-related coronary artery in patients with viability would reduce the occurrence of a composite end point of death, reinfarction, or unstable angina (UA).

Methods: Patients admitted with an (sub)acute myocardial infarction, who were not treated by primary or rescue PCI, and who were stable during the first 48 hours after the acute event, were screened for the study.

Effects of QRS duration and pacing location on pressure-volume loop evaluation of cardiac resynchronization therapy in end-stage heart failure.

Cardiac resynchronization therapy (CRT) decreases the morbidity and mortality in patients with end-stage heart failure. However, patient selection remains challenging, because a considerable 30% to 50% do not respond. Controversy exists on the cutoff values for the QRS duration and the optimal lead location.

Implementation of a prehospital triage system for patients with chest pain and logistics for primary percutaneous coronary intervention in the region of Amsterdam, the Netherlands.

We aimed to describe the logistics of a prehospital triage system for patients with acute chest pain in the region of Amsterdam, The Netherlands. Ambulance electrocardiograms (ECGs) were evaluated immediately in 1 of the percutaneous coronary intervention (PCI)-capable centers. Patients accepted for primary PCI (PPCI) were directly transferred to the catheterization laboratory.

Diastolic and systolic heart failure: different stages or distinct phenotypes of the heart failure syndrome?

It remains uncertain if diastolic heart failure (DHF) is a distinct HF phenotype or a precursor stage of systolic HF (SHF). The unimodal distribution of left ventricular ejection fraction (LVEF) in HF, depressed LV long-axis shortening in DHF, and progression to eccentric LV remodeling in hypertension favor DHF and SHF as successive stages. These arguments are countered by the bimodal distribution of LVEF after correction for gender, by the preserved LV twist in DHF and by the low incidence of eccentric LV remodeling in hypertension.

Distinct myocardial effects of beta-blocker therapy in heart failure with normal and reduced left ventricular ejection fraction.

Aims: Left ventricular (LV) myocardial structure and function differ in heart failure (HF) with normal (N) and reduced (R) LV ejection fraction (EF). This difference could underlie an unequal outcome of trials with beta-blockers in heart failure with normal LVEF (HFNEF) and heart failure with reduced LVEF (HFREF) with mixed results observed in HFNEF and positive results in HFREF. To investigate whether beta-blockers have distinct myocardial effects in HFNEF and HFREF, myocardial structure, cardiomyocyte function, and myocardial protein composition were compared in HFNEF and HFREF patients without or with beta-blockers.

Left ventricular torsion: an expanding role in the analysis of myocardial dysfunction.

During left ventricular (LV) torsion, the base rotates in an overall clockwise direction and the apex rotates in a counterclockwise direction when viewed from apex to base. LV torsion is followed by rapid untwisting, which contributes to ventricular filling. Because LV torsion is directly related to fiber orientation, it might depict subclinical abnormalities in heart function.

Hypophosphorylation of the Stiff N2B titin isoform raises cardiomyocyte resting tension in failing human myocardium.

High diastolic stiffness of failing myocardium results from interstitial fibrosis and elevated resting tension (F(passive)) of cardiomyocytes. A shift in titin isoform expression from N2BA to N2B isoform, lower overall phosphorylation of titin, and a shift in titin phosphorylation from N2B to N2BA isoform can raise F(passive) of cardiomyocytes. In left ventricular biopsies of heart failure (HF) patients, aortic stenosis (AS) patients, and controls (CON), we therefore related F(passive) of isolated cardiomyocytes to expression of titin isoforms and to phosphorylation of titin and titin isoforms.

Recurrent ventricular fibrillation caused by coronary artery spasm leading to implantable cardioverter defibrillator implantation.

Coronary artery spasm has been known to induce ischaemia and ventricular arrhythmias. We present a case of recurrent ventricular fibrillation caused by spasm-associated transmural myocardial ischaemia. During an intra-coronary acetylcholine provocation test, severe coronary spasm could be induced.

Myofilament degradation and dysfunction of human cardiomyocytes in Fabry disease.

Early detection of myocardial dysfunction in Fabry disease (FD) cardiomyopathy suggests the contribution of myofilament structural alterations. Six males with untreated FD cardiomyopathy submitted to cardiac studies, including tissue Doppler imaging and left ventricular endomyocardial biopsy. Active and resting tensions before and after treatment with protein kinase A (PKA) were determined in isolated Triton-permeabilized cardiomyocytes.

Diastolic stiffness of the failing diabetic heart: importance of fibrosis, advanced glycation end products, and myocyte resting tension.

Background: Excessive diastolic left ventricular stiffness is an important contributor to heart failure in patients with diabetes mellitus. Diabetes is presumed to increase stiffness through myocardial deposition of collagen and advanced glycation end products (AGEs). Cardiomyocyte resting tension also elevates stiffness, especially in heart failure with normal left ventricular ejection fraction (LVEF).

Right coronary artery flow impairment in patients with pulmonary hypertension.

Aims: This study investigates whether increased right ventricular (RV) pressure in pulmonary hypertension (PH) impairs right coronary artery (RCA) flow and RV perfusion.

Methods: In 25 subjects, five patients with idiopathic pulmonary arterial hypertension, nine patients with chronic thromboembolic pulmonary arterial hypertension, and 11 healthy controls, flow of the RCA and left anterior descending (LAD) artery was measured with MR flow quantification.

Results: In PH, RCA peak systolic and mean systolic flow were lower, 1.

High dose adenosine for suboptimal myocardial reperfusion after primary PCI: A randomized placebo-controlled pilot study.

Objectives: This study was designed to investigate the influence of high dose intracoronary adenosine on persistent ST-segment elevation after primary percutaneous coronary intervention (PCI).

Background: After successful PCI for acute myocardial infarction 40-50% of patients show persistent ST-segment elevation indicating suboptimal myocardial reperfusion. Adenosine has been studied to ameliorate reperfusion and is frequently used in a variety of doses, but there are no prospective studies to support its use for treatment of suboptimal reperfusion.

Right ventricular diastolic dysfunction and the acute effects of sildenafil in pulmonary hypertension patients.

Aims: This study investigated whether right ventricular (RV) diastolic function is impaired in pulmonary hypertension (PH) patients, and whether it is related to RV mass and afterload. In addition, the effects of an acute reduction of RV afterload by the oral intake of sildenafil were studied. Finally, we assessed whether diastolic function is related to cardiac parameters of disease severity.

Effects of aging on left atrioventricular coupling and left ventricular filling assessed using cardiac magnetic resonance imaging in healthy subjects.

Left ventricular (LV) filling results from diastolic suction of the left ventricle and passive left atrial (LA) emptying at early diastole and LA contraction at end-diastole. Effects of aging on LA and LV geometric characteristics and function and its consequences for LV filling are incompletely understood. Insight into these effects may increase the understanding of diastolic function.

Prognostic value of right ventricular mass, volume, and function in idiopathic pulmonary arterial hypertension.

Aims: This study investigated the relationship between right ventricular (RV) structure and function and survival in idiopathic pulmonary arterial hypertension (IPAH).

Methods And Results: In 64 patients, cardiac magnetic resonance, right heart catheterization, and the six-minute walk test (6MWT) were performed at baseline and after 1-year follow-up. RV structure and function were analysed as predictors of mortality.

Myocardial structure and function differ in systolic and diastolic heart failure.

Background: To support the clinical distinction between systolic heart failure (SHF) and diastolic heart failure (DHF), left ventricular (LV) myocardial structure and function were compared in LV endomyocardial biopsy samples of patients with systolic and diastolic heart failure.

Methods And Results: Patients hospitalized for worsening heart failure were classified as having SHF (n=22; LV ejection fraction (EF) 34+/-2%) or DHF (n=22; LVEF 62+/-2%). No patient had coronary artery disease or biopsy evidence of infiltrative or inflammatory myocardial disease.

Functional effects of protein kinase C-mediated myofilament phosphorylation in human myocardium.

Objective: In human heart failure beta-adrenergic-mediated protein kinase A (PKA) activity is down-regulated, while protein kinase C (PKC) activity is up-regulated. PKC-mediated myofilament protein phosphorylation might be detrimental for contractile function in cardiomyopathy. This study was designed to reveal the effects of PKC on myofilament function in human myocardium under basal conditions and upon modulation of protein phosphorylation by PKA and phosphatases.

Impaired left ventricular filling due to right-to-left ventricular interaction in patients with pulmonary arterial hypertension.

The aim of this study was to investigate the contribution of direct right-to-left ventricular interaction to left ventricular filling and stroke volume in 46 patients with pulmonary arterial hypertension (PAH) and 18 control subjects. Stroke volume, right and left ventricular volumes, left ventricular filling rate, and interventricular septum curvature were measured by magnetic resonance imaging and left atrial filling by transesophageal echocardiography. Stroke volume, left ventricular end-diastolic volume, and left ventricular peak filling rate were decreased in PAH patients compared with control subjects: 28 +/- 13 vs.

Matrix, cytoskeleton, or myofilaments: which one to blame for diastolic left ventricular dysfunction?

During cardiac filling, the relative contribution of distension of interstitial collagen, of distension of cytoskeletal proteins, and of low-grade diastolic cross-bridge cycling in the generation of diastolic left ventricular (LV) pressure remains unclear. In failing myocardium, interstitial collagen deposition and cross-linking are augmented. This increase in collagen deposition is accompanied by expression of a stiffer isoform of titin in the cardiomyocytes.