Dextrocardia
For the WikiDoc page for this topic, click here
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editors-In-Chief: Priyamvada Singh, MBBS [[2]]; Cafer Zorkun, M.D., Ph.D. [3]; Keri Shafer, M.D. [4]; Claudia Hochberg, M.D.; Assistant Editor-In-Chief: Kristin Feeney, B.S. [[5]]
| Dextrocardia | ||
 | ||
|---|---|---|
| ICD-10 | Q24.0 | |
| ICD-9 | 746.87 | |
| DiseasesDB | 3617 | |
| MeSH | C14.240.400.280 | |
Overview
'Dextrocardia refers to the heart being situated on the right side of the body. If all visceral organs are mirror reversed, the correct term is Dextrocardia Situs Inversus Totalis. Individuals with both dextrocardia and situs inversus have a lower incidence of congenital heart defects than do people with only one of the two conditions.
History
Dextorocardia was decribed by Fabricious in 1606. Situs inversus with dextrocardia (totalis) was first described by Severinus in 1643.
Epidemiology
Dextrocardia is believed to occur in approximately 1 in a 100 people, while 1 in 1,000 of these will have Situs Inversus.
Kartagener’s syndrome occurs in approximately 1 in 15-25 of patients with Totalis (situs inversus with dextrocardia). Kartagener Syndrome (KS), is a rare autosomal recessive genetic disorder caused by a defect in the action of the tiny hairs (cilia) lining the respiratory tract. Specifically, it is a defect in a gene coding for left-right dynein (lrd), a key structural protein in cilia.[1]
Pathophysiology
Dextrocardia is not associated with any medical sequela.
Diagnosis
Electrocardiogram
It is possible to distinguish lead reversal and dextrocardia by watching the precordial leads. Dextrocardia will show an R wave inversion, whereas lead reversal will not. The bottom EKG shows marked right axis deviation and loss of voltage across the precordium. There are also inverted P waves in leads I and aVL. The differential for inverted P waves in lead I and aVL is Dextrocardia vs Reversed Arm Leads. Since there is loss of voltage across the precordium this is Dextrocardia.
-
Right and left arm lead reversal can be distinguished from the (much rarer) dextrocardia by looking at the precordial R wave progression. -
EKG in a patient with dextrocardia. This EKG shows marked right axis deviation and loss of voltage across the precordium. There are also inverted p waves in leads I and aVL. The differential for inverted p waves in lead I and aVL is Dextrocardia or Reversed Arm Leads. Since there is loss of voltage across the precordium this is Dextrocardia.
Chest X Ray
Shown to the right is a chest X ray in a patient with Dextrocardia. Note that the heart is on the right side of the chest.
Coronary Angiography
- Dextrocardia Angiogram 1
<youtube v=r570-FIuVCc/>
- Dextrocardia Angiogram 2
<youtube v=Kd1LjLJWvTQ/>
- Dextrocardia Angiogram 3
<youtube v=rIQqCAgLk1Y/>
Fetal and Postnatal Diagnosis by Ultrasound, Magnetic Resonance Imaging (MRI), and Chest X Ray
The presenting twin of this 22 week gestation has dextrocardia. Images supported by NIH grant NS37945
Performing an EKG
ECG leads must be placed in reversed positions on a person with Dextrocardia.
Defibrillating a Patient with Dextrocardia
When defibrillating a patient with dextrocardia, the pads should be placed in reverse positions. That is, instead of upper right and lower left, pads should be placed upper left and lower right.
Treatment
Coronary Artery Bypass Grafting
CABG can be performed in the patient with dextrocardia. A right internal mammary artery may be used as a conduit to the left anterior descending artery.[2] [3] [4]
References
- ↑ Cleveland JC Jr, Shroyer AL, Chen AY, et al: Off-pump coronary artery bypass grafting decreases risk-adjusted mortality and morbidity. Ann Thorac Surg 2001;72: 1282-1289.
- ↑ Irvin RG, Ballenger JF: Coronary artery bypass in a patient with situs inversus. Chest 1982;81:380-381.
- ↑ Mesa JM, Aroca A, Frutos A, et al: Situs inversus and myocardial revascularization: Case report. J Cardiovasc Surg 1995;36: 571-572.
- ↑ Cleveland JC Jr, Shroyer AL, Chen AY, et al: Off-pump coronary artery bypass grafting decreases risk-adjusted mortality and morbidity. Ann Thorac Surg 2001;72: 1282-1289.