Left ventricular cavity obliteration: Mechanism of the intracavitary gradient and differentiation from hypertrophic obstructive cardiomyopathy.

BACKGROUND: Controversy surrounds the cause of the pressure gradient in patients with hypertrophic obstructive cardiomyopathy (HOCM). Left ventricular cavity obliteration (LVCO) was first described as the cause of the gradient but subsequently systolic anterior motion (SAM) of the mitral valve has been established as the cause. Nevertheless, the two gradients, though different in origin and significance, share similar characteristics. They both have a similar "dagger" profile, are obtained from the cardiac apex, are associated with a hyperdynamic left ventricle, and the gradients are worsened by Valsalva. The distinction has clinical relevance, because treating the intracavitary gradient (ICG) of LVCO as if it were a SAM-associated gradient associated with HOCM would be inappropriate and possibly harmful. MATERIALS AND METHODS: To clarify the cause and characteristics of the ICG in patients with LVCO in patients without HOCM, we assessed the extent and duration of cavity obliteration, and for differentiation, we compared the spectral profiles with patients with HOCM and severe aortic stenosis (AS). RESULTS: Higher ICG is associated with a greater extent and more prolonged apposition of LV walls, and smaller left ventricular cavity size. The spectral profile of patients with AS, HOCM, and LVCO is differentiated by the peak/mean gradient ratios of 2 or less, 2-3, and 3 or greater, respectively, in >90% of patients. Most patients with LVCO without HOCM or severe LVH have an ICG < 36 mm Hg. CONCLUSION: The magnitude of ICG is quantitatively associated with the extent and duration of LVCO. Spectral profiles of severe AS, HOCM, and LVCO can be differentiated by the peak/mean gradient ratio.

Variability in intensive care unit length of stay after liver transplant: Determinants and potential opportunities for improvement.

PURPOSE: Recovery after liver transplant (LT) requires extensive resources, including prolonged intensive care unit stays. The objective of this study was to use an assessment tool to determine if LT recipients remain in ICU beyond designated indications. METHODS: Records from 100 consecutive LTs performed in a single institution were retrospectively reviewed. An admission, discharge, and triage screening (ADT) tool was utilized to assess the indications for each ICU day. Data collected included demographics; pre-, intra-, and post-operative course; and complications. Days not meeting ADT criteria were considered additional ICU days. RESULTS: 100 patients: mean age 55 years (range 24-78 years) and mean MELD score 30 (range 6-47). Three recipients who died within one week were excluded. Forty-eight (49.5%) patients had a total of 75 additional days on initial ICU stay. Univariate analysis revealed no significant differences between patients with and without additional days. 12/97 (12.4%) patients returned to ICU including 5/48 and 7/49 with and without additional days. CONCLUSION: Nearly half of the LT recipients remained in ICU an average of 1.6 additional days. Monitoring of organ function appeared to be the most common reason. Opportunities to improve resource utilization could include transfer to an intermediate/progressive care ("step-down") unit.