Cardiac G-protein-coupled receptor kinase 2 ablation induces a novel Ca2+ handling phenotype resistant to adverse alterations and remodeling after myocardial infarction

G-protein-coupled receptor kinase 2 (GRK2) is a primary regulator of β-adrenergic signaling in the heart. G-protein-coupled receptor kinase 2 ablation impedes heart failure development, but elucidation of the cellular mechanisms has not been achieved, and such elucidation is the aim of this study.

Coronary stent choice in patients with acute myocardial infarction

A prompt reperfusion with primary percutaneous coronary intervention represents the current gold standard treatment for patients with acute myocardial infarction. In this setting, coronary stents have been shown to improve outcomes compared to plain angioplasty and are routinely used. However, the stent selection among patients with acute myocardial infarction is still a matter of some debate. An increased risk of very late (>1-year) stent thrombosis has been associated with the use of early-generation drug-eluting stents (DES), leading to concerns regarding the long-term safety of these devices. Newer-generation DES were developed with the aim of addressing this safety issue, and were recently investigated in a few randomized studies in patients with acute myocardial infarction. The objective of the present review is to summarize the accumulated evidence, to guide the stent selection in patients with acute myocardial infarction.

Different cardiac biomarkers to detect peri-procedural myocardial infarction in contemporary coronary stent trials: impact on outcome reporting

To assess the differential implications of cardiac biomarker type on peri-procedural myocardial infarction (PMI) reporting.

Fatal myocardial infarction at 4.5 years in a case of homozygous familial hypercholesterolaemia

Management of homozygous familial hypercholesterolaemia is notoriously difficult. For these patients, LDL apheresis is considered the treatment of choice. Treatment initiation is advocated generally from the age of seven years onwards (Thompson et al., Atherosclerosis 198:247-255, 2008). Here, we present the case of a young girl from a large inbred family of Turkish descent with homozygous familial hypercholesterolaemia and fatal outcome at the early age of 4(1/2) years.In conclusion, this case suggests that management of homozygous familial hypercholesterolaemia may require earlier and more aggressive treatment, including LDL apheresis before the age of seven years.

Extracorporeal membrane oxygenation as a bridge to diagnosis in a 20-month old girl with pulmonary hypertension and right ventricular failure

A 20-month old girl with severe pulmonary hypertension and cardiomegaly was admitted to the paediatric intensive care unit with right ventricular failure of unknown origin. Only after decompression of the heart chambers under extracorporeal membrane oxygenation (ECMO), did the pathognomonic membrane of Cor triatriatum become visible on echocardiography. The patient underwent successful surgical correction and subsequently cardiac function recovered completely. Cor triatriatum remains a rare congenital cardiac disorder with a variable presentation, often including recurrent respiratory infections before right-sided heart failure occurs. This case illustrates that ECMO can serve not only as a bridge to diagnosis, but can also facilitate correct diagnosis. Given the excellent outcome after surgical treatment, it is crucial that cardiologists rule out the possibility of cor triatriatum when assessing a child with unexplained pulmonary hypertension.

Cardiac troponins as indicators of acute myocardial damage in dogs

Cardiac troponin I (cTnI) and T (cTnT) have a high sequence homology across phyla and are sensitive and specific markers of myocardial damage. The purpose of this study was to evaluate the Cardiac Reader, a human point-of-care system for the determination of cTnT and myoglobin, and the Abbott Axsym System for the determination of cTnI and creatine kinase isoenzyme MB (CK-MB) in healthy dogs and in dogs at risk for acute myocardial damage because of gastric dilatation-volvulus (GDV) and blunt chest trauma (BCT). In healthy dogs (n = 56), cTnI was below detection limits (<0.1 microg/L) in 35 of 56 dogs (reference range 0-0.7 microg/L), and cTnT was not measurable (<0.05 ng/mL) in all but 1 dog. At presentation, cTnI, CK-MB, myoglobin, and lactic acid were all significantly higher in dogs with GDV (n = 28) and BCT (n = 8) than in control dogs (P < .001), but cTnT was significantly higher only in dogs with BCT (P = .033). Increased cTnI or cTnT values were found in 26 of 28 (highest values 1.1-369 microg/L) and 16 of 28 dogs (0.1-1.7 ng/mL) with GDV, and in 6 of 8 (2.3-82.4 microg/L) and 3 of 8 dogs (0.1-0.29 ng/mL) with BCT, respectively. In dogs suffering from GDV, cTnI and cTnT increased further within the first 48 hours (P < .001). Increased cardiac troponins suggestive of myocardial damage occurred in 93% of dogs with GDV and 75% with BCT. cTnI appeared more sensitive, but cTnT may be a negative prognostic indicator in GDV. Both systems tested seemed applicable for the measurement of canine cardiac troponins, with the Cardiac Reader particularly suitable for use in emergency settings.

Instant percutaneous closure of patent foramen ovale in patients with acute myocardial infarction and normal coronary arteries

Two young women with angiographically normal coronary arteries suffered an acute myocardial infarction. Both were found to have a patent foramen ovale (PFO), the likely pathway of a paradoxical embolus causing the infarction. The PFOs were diagnosed and closed percutaneously with an Amplatzer PFO Occluder during the emergency coronary angiography.

Collateral-flow measurements in humans by myocardial contrast echocardiography: validation of coronary pressure-derived collateral-flow assessment

AIMS: Myocardial blood flow (MBF) is the gold standard to assess myocardial blood supply and, as recently shown, can be obtained by myocardial contrast echocardiography (MCE). The aims of this human study are (i) to test whether measurements of collateral-derived MBF by MCE are feasible during elective angioplasty and (ii) to validate the concept of pressure-derived collateral-flow assessment. METHODS AND RESULTS: Thirty patients with stable coronary artery disease underwent MCE of the collateral-receiving territory during and after angioplasty of 37 stenoses. MCE perfusion analysis was successful in 32 cases. MBF during and after angioplasty varied between 0.060-0.876 mL min(-1) g(-1) (0.304+/-0.196 mL min(-1) g(-1)) and 0.676-1.773 mL min(-1) g(-1) (1.207+/-0.327 mL min(-1) g(-1)), respectively. Collateral-perfusion index (CPI) is defined as the rate of MBF during and after angioplasty varied between 0.05 and 0.67 (0.26+/-0.15). During angioplasty, simultaneous measurements of mean aortic pressure, coronary wedge pressure, and central venous pressure determined the pressure-derived collateral-flow index (CFI(p)), which varied between 0.04 and 0.61 (0.23+/-0.14). Linear-regression analysis demonstrated an excellent agreement between CFI(p) and CPI (y=0.88 x +0.01; r(2)=0.92; P<0.0001). CONCLUSION: Collateral-derived MBF measurements by MCE during angioplasty are feasible and proved that the pressure-derived CFI exactly reflects collateral relative to normal myocardial perfusion in humans.

The relative myocardial blood volume differentiates between hypertensive heart disease and athlete's heart in humans

AIMS: The adaptation of the myocardial microcirculation in humans to pathologic and physiologic stress has not been examined in vivo so far. We sought to test whether the relative blood volume (rBV) measured by myocardial contrast echocardiography (MCE) can differentiate between left ventricular (LV) hypertrophy (LVH) in hypertensive heart disease and athlete's heart. METHODS AND RESULTS: Four groups were investigated: hypertensive patients with LVH (n = 15), semi-professional triathletes with LVH (n = 15), professional football players (n = 15), and sedentary control individuals without cardiovascular disease (n = 15). MCE was performed at rest and during adenosine-induced hyperaemia. The rBV (mL mL(-1)), its exchange frequency (beta, min(-1)), and myocardial blood flow (mL min(-1) g(-1)) were derived from steady state and refill sequences of ultrasound contrast agent. Hypertensive patients had lower rBV (0.093 +/- 0.013 mL mL(-1)) than triathletes (0.141 +/- 0.012 mL mL(-1), P < 0.001), football players (0.129 +/- 0.014 mL mL(-1), P < 0.001), and sedentary individuals (0.126 +/- 0.018 mL mL(-1), P < 0.001). Conversely, the exchange frequency (beta) was significantly higher in hypertensive patients (11.3 +/- 3.8 min(-1)) than in triathletes (7.4 +/- 1.8 min(-1)), football players (7.7 +/- 2.3 min(-1)), and sedentary individuals (9.0+/-2.5 min(-1)). An rBV below 0.114 mL mL(-1) distinguished hypertensive patients and triathletes with a sensitivity of 93% and a specificity of 100%. CONCLUSION: Pathologic and physiologic LVH were differentiated non-invasively and accurately by rBV, a measure of vascularisation assessed by MCE.

Safety and outcome of patients with an acute ST-elevation myocardial infarction transferred for primary coronary intervention: the Neuchâtel experience

BACKGROUND: Transferring patients with ST-elevation myocardial infarction (STEMI) for primary percutaneous coronary intervention (PCI) from a community hospital to a PCI centre has been evaluated in randomised trials and shown to be safe and effective. A prolonged transfer time may restrict the benefit of this strategy. AIM: We sought to assess 1) safety of transfer from Neuchâtel to Berne, 2) time intervals of patients transferred either directly from on-site or after evaluation in the local emergency room, and 3) clinical long-term outcome. METHODS AND RESULTS: 42 patients with STEMI eligible for reperfusion therapy were prospectively included between January 2003 and June 2004. Twenty patients (48%, group 1) were directly transferred to the PCI centre from on-site. Twenty-two were transferred after initial treatment in the local emergency room: 11 patients (26%, group 2) presented spontaneously at the hospital and 11 patients (26%, group 3) were admitted by the rescue team. No major complication occurred during transport. Median transport time was 33 minutes. Median time from first healthcare contact to balloon consisted of 131 minutes in group 1, 158 minutes in group 2 and 174 minutes in group 3. The overall rate of Major Adverse Cardiac Events (MACE) at 6 months amounted to 9.5%. CONCLUSIONS: Transfer for primary PCI of our patients with acute STEMI was safe. Direct transfer from on-site to the PCI centre reduced the time of ischaemia. The overall MACE rate was low.