Pathophysiology of left-to-right shunts
- Grace C Kung, MD
Grace C Kung, MD
- Associate Professor of Pediatrics
- University of Southern California Keck School of Medicine
- John K Triedman, MD
John K Triedman, MD
- Section Editor — Pediatric Cardiology
- Professor of Pediatrics
- Harvard Medical School
In conditions with left-to-right shunt, blood from the systemic arterial circulation mixes with systemic venous blood. Multiple factors influence the extent of flow through the shunt and its physiologic effects.
The pathophysiology of left-to-right shunts is reviewed here. The evaluation and management of specific cardiac lesions are discussed separately, including:
●Atrial level shunts (see "Classification of atrial septal defects (ASDs), and clinical features and diagnosis of isolated ASDs in children" and "Identification and assessment of atrial septal defects in adults" and "Patent foramen ovale" and "Partial anomalous pulmonary venous connection" and "Total anomalous pulmonary venous connection")
●Ventricular level shunts (see "Pathophysiology and clinical features of isolated ventricular septal defects in infants and children" and "Ventricular septal defect in adults" and "Pathophysiology, clinical features, and diagnosis of tetralogy of Fallot")
●Patent ductus arteriosus (see "Clinical manifestations and diagnosis of patent ductus arteriosus in term infants, children, and adults" and "Pathophysiology, clinical manifestations, and diagnosis of patent ductus arteriosus in premature infants")
Subscribers log in hereLiterature review current through: Sep 2017. | This topic last updated: Sep 06, 2017.References
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- FETAL AND TRANSITIONAL CIRCULATION
- Shunt size
- Pulmonary effects
- Neurohumoral activation
- Metabolic effects
- Pulmonary hypertension
- CLINICAL MANIFESTATIONS
- Respiratory effects
- Pulmonary infections
- Poor growth
- Time of presentation
- CAUSES OF SHUNTING
- Atrial level shunts
- Ventricular level shunts
- - Small VSDs
- - Moderate VSDs
- - Large VSDs
- Associated lesions
- Changes during cardiac cycle
- Arterial level shunts
- OTHER INFLUENCES ON SHUNTING
- Other cardiac lesions
- Increased PVR