ABSTRACT
Acute myocarditis is an inflammatory disorder of the myocardium associated with cardiac dysfunction. The definition of myocarditis varies, but the Dallas criteria for myocarditis requires an inflammatory infiltrate and associated myocyte necrosis or damage not characteristic of an ischaemic event. Here we present a case of acute myocarditis in a 48-year-old woman masquerading as acute coronary syndrome. Patients with myocarditis usually have normal coronary arteries and we discuss diagnostic difficulties when it presents with 'true' acute coronary syndrome. In this case, cardiovascular magnetic resonance played an important role in the diagnosis of our patient and follow-up.
Subject(s)
Delayed Diagnosis , Myocarditis/diagnosis , Ventricular Dysfunction, Left/diagnosis , Acute Disease , Contrast Media , Female , Gadolinium , Humans , Magnetic Resonance Imaging , Middle Aged , Myocarditis/complications , Shock, Cardiogenic/etiology , Ventricular Dysfunction, Left/etiologyABSTRACT
This article reports the case of a patient who developed a sudden impairment of gas exchange, renal function and a distended abdomen 13 days after admission to the intensive care unit. The combination of a sudden platelet drop, the timing of heparin administration and evidence of thromboembolic events by computed tomography (CT) led to the suspected diagnosis of heparin-induced thrombocytopenia (HIT) type II which was confirmed by laboratory testing. HIT is a life-threatening complication of heparin anticoagulation and CT is an important diagnostic instrument for detecting the location and extent of thromboembolic manifestations, thereby enabling the initiation of therapy to prevent further complications.
Subject(s)
Brain Injuries/complications , Brain Injuries/therapy , Heparin/adverse effects , Heparin/therapeutic use , Thrombocytopenia/chemically induced , Thrombocytopenia/diagnosis , Tomography, X-Ray Computed/methods , Anticoagulants/adverse effects , Anticoagulants/therapeutic use , Humans , Male , Middle Aged , Radiography, Abdominal/methods , Thrombocytopenia/prevention & controlABSTRACT
BACKGROUND: Apelin, the endogenous ligand for the novel G protein-coupled receptor APJ, has major cardiovascular effects in preclinical models. The study objectives were to establish the effects of acute apelin administration on peripheral, cardiac, and systemic hemodynamic variables in healthy volunteers and patients with heart failure. METHODS AND RESULTS: Eighteen patients with New York Heart Association class II to III chronic heart failure, 6 patients undergoing diagnostic coronary angiography, and 26 healthy volunteers participated in a series of randomized, double-blind, placebo-controlled studies. Measurements of forearm blood flow, coronary blood flow, left ventricular pressure, and cardiac output were made by venous occlusion plethysmography, Doppler flow wire and quantitative coronary angiography, pressure wire, and thoracic bioimpedance, respectively. Intrabrachial infusions of (Pyr(1))apelin-13, acetylcholine, and sodium nitroprusside caused forearm vasodilatation in patients and control subjects (all P<0.0001). Vasodilatation to acetylcholine (P=0.01) but not apelin (P=0.3) or sodium nitroprusside (P=0.9) was attenuated in patients with heart failure. Intracoronary bolus of apelin-36 increased coronary blood flow and the maximum rate of rise in left ventricular pressure and reduced peak and end-diastolic left ventricular pressures (all P<0.05). Systemic infusions of (Pyr(1))apelin-13 (30 to 300 nmol/min) increased cardiac index and lowered mean arterial pressure and peripheral vascular resistance in patients and healthy control subjects (all P<0.01) but increased heart rate only in control subjects (P<0.01). CONCLUSIONS: Acute apelin administration in humans causes peripheral and coronary vasodilatation and increases cardiac output. APJ agonism represents a novel potential therapeutic target for patients with heart failure.
Subject(s)
Cardiac Output/drug effects , Coronary Circulation/drug effects , Heart Failure/drug therapy , Intercellular Signaling Peptides and Proteins/administration & dosage , Regional Blood Flow/drug effects , Acetylcholine/administration & dosage , Chronic Disease , Female , Forearm/blood supply , Humans , Injections, Intravenous , Male , Middle Aged , Myocardial Contraction/drug effects , Nitroprusside/administration & dosage , Plethysmography , Vasodilation/drug effects , Vasodilator Agents/administration & dosage , Ventricular Pressure/drug effectsABSTRACT
Static colonic mechanical properties are characterized by stepwise balloon distention. It is unclear whether the state of contractile activation affects frequency-dependent differences in biomechanical properties. Our aim was to investigate the frequency-dependence of colonic mechanical properties by sinusoidal oscillation. A descending colonic balloon was sinusoidally oscillated by 25 mL at 5, 10 and 20 cpm in randomized order for 20 min at each frequency in six healthy subjects before and after neostigmine. Volume oscillation was between 75-100 mL before, and 25-50 mL after neostigmine. Pressure waveforms were most variable shortly after commencing oscillation, reflecting an initial contractile response to distention. Elastance (i.e. pressure response to imposed volume) and hysteresivity were estimated; hysteresivity represents the proportion of energy added to the system during inflation, which cannot be recovered during deflation. Colonic elastance was frequency dependent, being highest and most variable at 10 cpm. In contrast, hysteresivity was not significantly different across frequencies. Neostigmine increased mean colonic elastance at all frequencies, and hysteresivity only at 5 cpm. Thus, colonic mechanical properties, particularly elastance are frequency-dependent. The frequency-dependence of colonic mechanical properties is worthy of future study because it may provide insights into reflex responses in health and disease.
