Intracardiac echocardiography (ICE) allows cardiologists to visualize cardiac structures (aorta, valves, pulmonary veins, chambers, etc) from an ultrasound catheter usually threaded into the right atrium (RA) or right ventricle (RV) from the femoral vein. It aids in procedures ranging from percutaneous valve replacement and ablation to septal defect closures by…
The mitral valve (MV) separates the left atrium (LA) and left ventricle (LV). It’s a bileaflet valve composed of an anterior and posterior leaflet, each with three “scallops” designated A1, A2, A3, P1, P2, and P3. The A3-P3 interface tapers into the posteromedial commissure whereas the A1-P1 interface becomes the…
Mechanical circulatory support (MCS) devices allow us to offload myocardial work from the heart, and for the purposes of this post, the left ventricle (LV). Referring to my previous post on the work of breathing, we can extrapolate the same pressure-volume (PV) loop integral to represent work, except in this…
Left ventricular outflow tract (LVOT) obstruction is a potentially catastrophic etiology for hypotension due to several etiologies: idiopathic hypertrophic subaortic stenosis (IHSS), hypertrophic obstructive cardiomyopathy (HOCM), systolic anterior motion (SAM) of the mitral valve, and even mid-cavity obstructive hypertrophic cardiomyopathy. These obstructions can be dynamic in nature and consequently vary…
Impella® is a percutaneous axial heart pump placed retrograde across the aortic valve into the left ventricle (LV) utilizing fluoroscopy +/- echocardiography. Its indications include high-risk percutaneous coronary intervention (PCI, especially cardiogenic shock or signs of ongoing ischemia), post-cardiotomy failure, and myocarditis. In addition, it is routinely used as a…
This post outlines the steps in traditional, central cannulation for cardiopulmonary bypass (CPB). Depending on the nature of the surgery and the patient’s comorbidities, other sites are often cannulated (left heart bypass, femoral-femoral peripheral cannulation, etc.)
Heart muscle cells (cardiomyocytes) can undergo physiologic and pathologic remodeling when faced with differing hemodynamic loads and neurohormonal environments.
Normal cardiac conduction propagates downward and leftward from the SA node to the His-Purkinje system. Thus, lead I (points to the patient’s left) and lead aVF (points straight down) represent the component vectors in the x and y planes, respectively, for the cardiac conduction axis. This means that downward is + for lead aVF, and…