==[[Cardimegaly differential diagnosis|Differential diagnosis of cardiomegaly]]==
==[[Cardiomegaly differential diagnosis|Differential diagnosis of cardiomegaly]]==
In alphabetical order. <ref>Sailer, Christian, Wasner, Susanne. Differential Diagnosis Pocket. Hermosa Beach, CA: Borm Bruckmeir Publishing LLC, 2002:77 ISBN 1591032016</ref> <ref>Kahan, Scott, Smith, Ellen G. In A Page: Signs and Symptoms. Malden, Massachusetts: Blackwell Publishing, 2004:68 ISBN 140510368X</ref>
* [[Left ventricular hypertrophy]] or [[Left ventricular dilation]]
* [[Mitral stenosis]]
* [[Pickwickian Syndrome]]
* [[Pulmonic regurgitation]]
* [[Pulmonic stenosis]]
* [[Tetralogy of Fallot]]
* [[Transposition of the Great Vessels]]
* [[Tricuspid regurgitation]]
* [[Ventricular septal defect]]
== Diagnosis ==
== Diagnosis ==
[[Cardiomegaly history and symptoms|History and Symptoms]] | [[Cardiomegaly physical examination|Physical examination]] | [[Cardiomegaly laboratory tests|Lab tests]] | [[Cardiomegaly electrocardiogram|Electrocardiogram]] |
=== History and Symptoms ===
* In the history, the physician should inquire as to:
*:* History of [[chest pain]] to suggest [[ischemic heart disease]]
*:* History of [[rheumatic fever]] or known [[valvular heart disease]]
*:* History of [[congenital heart disease]]
*:* History of [[drug]] and [[alcohol]] use (recreational)
*:* [[Family history]] (heart disease or sudden death)
* Associated symptoms:
*:* [[Dizziness]]
*:* [[Syncope]]
*:* [[Fatigue]]
*:* [[Dyspnea]]
*:* [[Palpitation]]s
=== Physical Examination ===
=== Heart ===
There is downward and leftward displacement of the heart on percussion of heart border. The heart should be percussed with the patient supine and the head of the bed elevated 30 degrees.
Normally the left heart border should not
*Extend left of the mid clavicular line
*Extend more than 10 cm to the left of the mid sternal line
*Occupy a diameter > 3 cm
*Extend below the 5th intercostal space
The body habitus of the individual must be taken into account in performing the examination. In athletic individuals who are thin, the impulse maybe strongly transmitted. In muscular or obese patients, the opposite is true. In patients with [[pectus excavatum]], the apex can be displaced laterally.
== Laboratory Findings ==
Based upon the history and physical, a standard evaluation might include:
Common high yield tests:
* [[Complete blood count]] ([[CBC]]): to rule out [[anemia]]
* [[Erythrocyte sedimentation rate]] ([[ESR]]): to evaluate autoimmune causes
* [[Calcium]]: to rule out [[hypocalcemia]]
* [[Magnesium]]: to rule out [[hypomagnesemia]]
* [[Rheumatoid factor]]
* [[Antinuclear antibody]] ([[ANA]])
* [[Glucose]]
* [[Pheochromocytoma]] screening
* [[Phosphorus]]: to rule out [[hypophosphatemia]]
* [[Blood culture]]s
=== Electrolyte and Biomarker Studies ===
* [[Electrolyte]]s should be periodically checked in the patient treated with a [[diuretic]] to avoid [[hypokalemia]].
* [[Brain Natriuretic Peptide]] ([[BNP]]) levels may provide insight into the ongoing magnitude of LV dysfunction.
=== Electrocardiogram ===
*The presence of [[q wave]]s suggest a prior [[MI]] to account for the enlargement.
*[[ST segment elevation]] would suggest either ongoing or resolving [[ST Elevation Myocardial Infarction]] or [[Myocarditis]] or [[Pericarditis]].
*The EKG may suggest signs of [[left atrial enlargement]], [[right atrial enlargement]] or [[right axis deviation]] which may point toward a specific diagnosis.
Cardiomgaly is traditionally defined as an increase in the cardiothoracic ratio to be > 0.5 on a PA film. To calculate the thoracic ratio, the width of the cardiac silhouette is divided by the width of the entire thoracic cage.
If the heart is viewed on an AP film, the heart can appear to be artificially enlarged because the X ray beam moves from anterior to posterior direction and therefore the heart which lies anterior is magnified.
Postero Anterior (PA) Projection: adult heart is 12 cm from base to apex and 8-9 cm in transverse direction
Lateral Projection: The adult heart is 6 cm in the Antero Posterior (AP) direction
X-ray findings for left ventricular enlargement
Left heart border is displaced leftward, inferiorly, or posteriorly.
Rounding of the cardiac apex
Cardiomegaly. Image courtesy of C. Michael Gibson MS. MD
Posterior displacement of the left main stem bronchus on lateral radiograph
Superior displacement of the left main stem bronchus on frontal view
Posterior displacement of a barium filled esophagus
Double density sign
Double density sign
X-ray findings for right ventricular enlargement
Frontal view
Rounded left heart border
Uplifted apex
Lateral view
Filling of the retrosternal space
Rotation of the heart posteriorly
X-ray findings for right atrial enlargement
On a frontal view, the right atrium is visible because of its interface with the right middle lobe.
Subtle and moderate right atrial enlargement is not accurately determined on plain films because there is normal variability in the shape of the right atrium.
Echocardiography or Ultrasound
Echocardiogram recommended for those patients presenting suspected valvular disease, chamber size, ventricular function, and wall motion abnormalities
Other Diagnostic Studies
Exercise or pharmacologic stress testing may be indicated in those patients suspected of having coronary artery disease
A combination of diuretics and angiotensin converting enzyme (ACE) inhibition is currently the standard of care. Digoxin may reduce the frequency of rehospitalization, but does not improve mortality.
Surgery and Device Based Therapy
In patients who are awaiting a transplant for end-stage symptomatic heart failure, implantable ventricular assist devices may serve as a temporary aid for compensation.
Gross excellent example of concentric left ventricular hypertrophy
Left Ventricular Hypertrophy: Gross natural color anterior view intact heart showing disproportionate size of left ventricle by its inferior extent much below the right ventricle apex (quite good example)
Myocardial Infarct: Gross natural color apical section showing large left ventricle infarct and right ventricular hypertrophy
