How Can a Large Left Atrial Myxoma Cause a Selective Mid-Diastolic Right-to-Left Atrial Shunt?

Cardiac magnetic resonance imaging and a rare case of an atrial myxoma causing an atrial septal defect

A 40 year-old athletic woman presented with worsening dyspnea on exertion over the preceding several months. Chest radiograph showed borderline cardiomegaly and subsequent echocardiography demonstrated a 5.0-cm left atrial mass as well as left-to-right interatrial shunting through a patent foramen ovale. Cardiac magnetic resonance imaging was performed, which demonstrated signal characteristics consistent with an atrial myxoma. The patient then underwent urgent surgical treatment with good technical and clinical outcome. Histologic examination confirmed an atrial myxoma. Cardiac magnetic resonance imaging was valuable in characterizing the nature of the atrial mass and patent foramen ovale, helping guide the surgical approach.

Diagnostic Bedside Ultrasonography for Acute Respiratory Failure and Severe Hypoxemia in the Medical Intensive Care Unit: Basics and Comprehensive Approaches

Bedside goal-directed ultrasound is a powerful tool for rapid differential diagnosis and monitoring of cardiopulmonary disease in the critically ill patient population. The bedside intensivist is in a unique position to integrate ultrasound findings with the overall clinical situation. Medically critically ill patients who require urgent bedside diagnostic assessment fall into 2 categories: (1) acute respiratory failure and (2) hemodynamic derangements. The first portion of this review outlines the diagnostic role of bedside ultrasound in the medically critically ill patient population for the diagnosis and treatment of acute respiratory failure, acute respiratory distress, and severe hypoxemia. The second portion will focus on the diagnostic role of ultrasound for the evaluation and treatment of shock states, as well as describe protocolized approaches for evaluation of shock during cardiopulmonary resuscitation. Different respiratory system pathologies that result in acute respiratory failure (such as increased interstitial fluid, alveolar consolidation, pleural effusion) cause characteristic ultrasonographic findings; diaphragmatic assessment may also add information. Intracardiac shunting can cause severe hypoxemia. Protocolized approaches for the evaluation of patients with acute respiratory failure or distress are discussed.