Syncope from dynamic left ventricular outflow tract obstruction simulating hypertrophic cardiomyopathy in a patient with primary AL-type amyloid heart disease.

Dynamic left ventricular outflow tract (LVOT) obstruction is seen classically in hypertrophic cardiomyopathy. Cardiac amyloidosis can present with asymmetric hypertrophy that resembles hypertrophic cardiomyopathy, and, in some cases, with dynamic LVOT obstruction. The occurrence of syncope in such patients is not uncommon.

Validation of a new formula for mean arterial pressure calculation: the new formula is superior to the standard formula.

Mean arterial pressure (MAP) has traditionally been derived from systolic and diastolic pressures, weighted 1/3 systolic and 2/3 diastolic. No correction is made for the increasing time dominance of systole with increasing heart rates. In a previous study, we developed a new and more accurate heart rate-corrected MAP formula from central aorta pressure determinations in a large number of patients: MAP = DP + [0.

Severe methemoglobinemia after transesophageal echocardiography.

Methemoglobinemia, an increased concentration of methemoglobin in the blood, is an altered state of hemoglobin whereby the ferrous form of iron is oxidized to the ferric state, rendering the heme moiety incapable of carrying oxygen. This can cause hypoxia, cyanosis, or even death. Severe methemoglobinemia resulting from oral benzocaine spray before endoscopic procedures has been reported as a rare complication.

Sodium-hydrogen exchange inhibition during ventricular fibrillation: Beneficial effects on ischemic contracture, action potential duration, reperfusion arrhythmias, myocardial function, and resuscitability.

Background: Inhibition of the sarcolemmal sodium-hydrogen exchanger isoform-1 (NHE-1) is emerging as a promising novel strategy for ameliorating myocardial injury associated with ischemia and reperfusion. We investigated whether NHE-1 inhibition (with cariporide) could minimize mechanical and electrical myocardial abnormalities that develop during ventricular fibrillation (VF) and improve outcome using a porcine model of closed-chest resuscitation.

Methods And Results: Two groups of 8 pigs each were subjected to 8 minutes of untreated VF and randomized to receive either a 3-mg/kg bolus of cariporide or 0.