Tricuspid Regurgitation Causing a Right to Left Interatrial Shunt with Normal Pulmonary Pressures

Abstract

We describe a patient who presented with asymptomatic hypoxia refractory to supplemental oxygen. Transthoracic echocardiography and angiography demonstrated a tricuspid valve with a large regurgitant jet oriented directly at a patent foramen ovale, producing a right to left shunt with systemic hypoxia. The patient was found to have normal right-sided cardiac pressures as well as normal pulmonary arterial pressures, demonstrating the shunt was secondary to the tricuspid regurgitant jet and not a result of a pressure gradient between atria. Surgical correction of the tricuspid valve and closure of the patent foramen ovale resulted in resolution of the patient’s hypoxemia.

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

“…80 This is especially likely when the Eustachian valve persists after fetal cardiac development (either as prominent Eustachian valve or as Chiari network; Figure 19; Supplemental Video 18) but can also happen when a tricuspid regurgitant jet is directed against the interatrial septum. 81 The resulting RA flow pattern is referred to as a persistent embryonic RA flow pattern (Figure 20; Supplemental Video 19). 82 When the right atrium is further distorted mechanically, the Acute occlusion of pulmonary vascular bed: Thromboembolism 48 Bone marrow embolism 49 Red cell sickling Leukemic cell aggregates Air Other substances injected into systemic veins, that is, sclerosing agents, chemotherapeutic agents 50,51 Change in mediastinal anatomic constellation: Pneumonectomy or lobectomy, especially of the right lung 62 Pulmonary collapse therapy for pulmonary tuberculosis 63 Atelectasis Hemidiaphragm elevation 64 Kyphosis 65 Acute reduction of pulmonary vascular bed diameter: Increased intrathoracic pressure, that is, mechanical ventilation 52 Bronchospasm, that is, anaphylaxis, asthma/chronic obstructive pulmonary (disease COPD) exacerbation 53 Cardiac impingement of mediastinal structures: Thoracic aortic aneurysm, especially at the aortic root 66,67 Pulmonary vasoconstriction: Hypoxia 54 Acidosis Hypercapnia 55 Change in pericardial anatomic constellation: Pericardial effusion Drainage of pericardial effusion 68,69 Acutely decreased right ventricular systolic function: Right ventricular myocardial ischemia/infarction 56 Right ventricular dysfunction after pericardiocentesis 57 Medication-induced myocardial depression 58 Stress cardiomyopathy Septic cardiomyopathy…”

“…80 This is especially likely when the Eustachian valve persists after fetal cardiac development (either as prominent Eustachian valve or as Chiari network; Figure 19; Supplemental Video 18) but can also happen when a tricuspid regurgitant jet is directed against the interatrial septum. 81 The resulting RA flow pattern is referred to as a persistent embryonic RA flow pattern (Figure 20; Supplemental Video 19). 82 When the right atrium is further distorted mechanically, the portion of inferior vena caval flow that is directed onto the interatrial septum can increase.…”

Stepwise Progression of Right-to-Left Atrial Shunting through a Combination of Patent Foramen Ovale and Tricuspid Regurgitation

“…Multiple causes of RV dysfunction have been associated with right-toleft shunting, including RV infarction, carcinoid syndrome, cardiomyopathy, and TR. [6][7][8][9] Our patient had a known PFO and developed pacemaker-related TR. She initially presented with mild symptoms due predominantly to volume overload from the TR, but her symptoms progressed and she presented with upright hypoxemia (platypnea-orthodeoxia).…”