History

Fact Explanation
Fatigue[1] In this disease, the left ventricle is dilated, and more spherical than usual with raised wall stress and depressed systolic function. When the disease progressed with time patient develop signs and symptoms of heart failure. Exertional fatigue occurs due to the under - perfusion of the skeletal muscles.[3]
Shortness of breath on exercion[1] In dilated cardiomyopathy the left ventricle is dilated and the ejection fraction is reduced which leads to the pulmonary congestion and reduced blood gas exchange.[4]
Orthopnea[1] When the patient is lying down pulmonary congestion increases upto a level where the patient feels difficulty in breathing when lying down and but it gets relieved in a sitting up position.[1]
Peripheral odema[1] When the heart fails to maintain cardiac output and peripheral tissue perfusion there is expansion of extracellular fluid volume secondary to the salt and water retention. [5]
Chest pain [1] Occurs due to ischemia. Elevated filling pressures, increased heart rate, decreased coronary perfusion pressure, and increasing left ventricular mass out of proportion to microvasculature cause ischemia.[7]
Sudden cardiac death[1], [6] Due to the dilation of the heart, normal architecture of the cardiac muscle is disrupted and conduction tissues system get disorganize and cause ventricular fibrillation. [6]
Family history[1] Familial dilated cardiomyopathy has a genetic basis. Therefore in the history it is important to know about family history of cardiomyopathy or any unexplained sudden death.
History of hypertention[8] In hypertension cardiac muscle remodeling occurs therefore patient with a history of hypertension has an increased risk of developing dilated cardiomyopathy.[8]
History of thyrotoxicosis [9] The heart is sensitive to changes in thyroid hormones, and cardiac disorders are commonly associated with both hyper- or hypothyroidism. Left ventricular systolic function is minimally decreased with slightly reduced ejection fraction and stroke volume due to thyroid levels and dilated cardiomyopathy can be a rare presentation of hyper/hypothyroidism. [9]
History of anaemia [10] Low hemoglobin levels are associated with worsening heart failure and cardiac dysfunction. Therefore it is important to know about patients history of anaemia. [10]
Alcohol intake[1], [11] Chronic alcohol abuse is one of the most important adult causes of this disease in developed countries. therefore it is important to know about alcohol consumption of the patient. [1], [11]
References
  1. JEFFERIES JOHN LYNN, TOWBIN JEFFREY A. Dilated cardiomyopathy. The Lancet [online] 2010 February, 375(9716):752-762 [viewed 25 June 2014] Available from: http://mail.elsevier-alerts.com/AEM/Clients/ELA001/2010/dilatedcardiomyopathy.pdf
  2. NELSON G. S., BERGER R. D., FETICS B. J., TALBOT M., SPINELLI J. C., HARE J. M., KASS D. A.. Left Ventricular or Biventricular Pacing Improves Cardiac Function at Diminished Energy Cost in Patients With Dilated Cardiomyopathy and Left Bundle-Branch Block. Circulation [online] 2000 December, 102(25):3053-3059 [viewed 25 June 2014] Available from: doi:10.1161/​01.CIR.102.25.3053
  3. WILSON J. R., MANCINI D. M., DUNKMAN W. B.. Exertional fatigue due to skeletal muscle dysfunction in patients with heart failure. Circulation [online] 1993 February, 87(2):470-475 [viewed 25 June 2014] Available from: doi:10.1161/​01.CIR.87.2.470
  4. DIAZ RA, OBASOHAN A, OAKLEY CM. Prediction of outcome in dilated cardiomyopathy. Br Heart J [online] 1987 Oct, 58(4):393-399 [viewed 25 June 2014] Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1277273
  5. DZAU V. J., COLUCCI W. S., HOLLENBERG N. K., WILLIAMS G. H.. Relation of the renin-angiotensin-aldosterone system to clinical state in congestive heart failure. Circulation [online] 1981 March, 63(3):645-651 [viewed 25 June 2014] Available from: doi:10.1161/​01.CIR.63.3.645
  6. BANSCH D.. Primary Prevention of Sudden Cardiac Death in Idiopathic Dilated Cardiomyopathy: The Cardiomyopathy Trial (CAT). [online] December, 105(12):1453-1458 [viewed 25 June 2014] Available from: doi:10.1161/​01.CIR.0000012350.99718.AD
  7. TREASURE C. B., VITA J. A., COX D. A., FISH R. D., GORDON J. B., MUDGE G. H., COLUCCI W. S., SUTTON M. G., SELWYN A. P., ALEXANDER R. W.. Endothelium-dependent dilation of the coronary microvasculature is impaired in dilated cardiomyopathy. Circulation [online] 1990 March, 81(3):772-779 [viewed 26 June 2014] Available from: doi:10.1161/​01.CIR.81.3.772
  8. KEELING PJ, GANG Y, SMITH G, SEO H, BENT SE, MURDAY V, CAFORIO AL, MCKENNA WJ. Familial dilated cardiomyopathy in the United Kingdom. Br Heart J [online] 1995 May, 73(5):417-421 [viewed 26 June 2014] Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC483856
  9. SEOL MD, LEE YS, KIM DK, CHOI YH, KIM DJ, PARK SH, CHO HJ, CHO WH. Dilated Cardiomyopathy Secondary to Hypothyroidism: Case Report with a Review of Literatures J Cardiovasc Ultrasound [online] 2014 Mar, 22(1):32-35 [viewed 26 June 2014] Available from: doi:10.4250/jcu.2014.22.1.32
  10. HORWICH TAMARA B, FONAROW GREGG C, HAMILTON MICHELE A, MACLELLAN W.ROBB, BORENSTEIN JEFF. Anemia is associated with worse symptoms, greater impairment in functional capacity and a significant increase in mortality in patients with advanced heart failure. Journal of the American College of Cardiology [online] 2002 June, 39(11):1780-1786 [viewed 26 June 2014] Available from: doi:10.1016/S0735-1097(02)01854-5
  11. LUCAS DIANE L., BROWN RICARDO A., WASSEF MOMTAZ, GILES THOMAS D.. Alcohol and the Cardiovascular System. Journal of the American College of Cardiology [online] 2005 June, 45(12):1916-1924 [viewed 26 June 2014] Available from: doi:10.1016/j.jacc.2005.02.075

Examination

Fact Explanation
Tachypnoea[1] In dilated cardiomyopathy due to the dilation of the left ventricle there is a systolic dysfunction and respiratory gas exchange is impaired. In order to maintain adequate perfusion as an adaption respiratory rate increases.[1],[2]
Tachycardia[1] Due to the dilation of the heart adequate stroke volume can not be maintained. Therefore to maintain the adequate cardiac output heart rate has to be increased. Other than that tachyarrhythmias due to the disruption of normal architecture of the cardiac muscle also cause tachycardia.[1],[3]
Hypertension[1] Decrease in the cardiac output causes impaired tissue perfusion, which causes activation of neurohormonal mechanisms as RAAS(Renin angiotensin activation system). That will lead to the sympathetic activation and sodium and water retention.[4]
Elevated jugular venous pressure[5] External or internal jugular vein may be useful in the assessment of mean venous pressure and pulse contour. In dilated cardiomyopathy due to the volume overload jugular venous pressure gets elevated.[6]
Ascites[7] Left ventricular dilation in this disease will lead to the right heart failure and volume overload due to the neurohormonal and other compensatory mechanisms.[7]
Peripheral edema [1] When heart fails to maintain cardiac output and peripheral tissue perfusion there is expansion of extracellular fluid volume secondary to the salt and water retention.[8]
Shifting of the cardiac apex [1] Due to the dilation of the left ventricle apex of the heart is deviated to the left.[1]
Parasternal heave[1] Occurs due to the right ventricular hypertrophy and pulmonary hypertension which is caused by prolong dysfunction of the dilated left ventricle.[9]
Paradoxical splitting of the s2 [1] In this splitting of s2 occurs in expiration and pulmonary valve close before the aortic valve [1]
s3, s4 [1] s3 - Best heard at the apex, occurs due to the left ventricular dysfunction s4 - Left sided s4 which is often palpable is due to impaired left ventricular relaxation. Rarely right side s4 occurs in right ventricular dysfunction.[1]
Murmur[10] Murmur occur due to the functional mitral regurgitation because of the dilatation of mitral annulus and to retraction of the leaflets by chordae and papillary muscles as the left ventricle dilates. Murmur - pan systolic murmur, best heard at the apex with radiating to the axilla. [10]
References
  1. JEFFERIES JOHN LYNN, TOWBIN JEFFREY A. Dilated cardiomyopathy. The Lancet [online] 2010 February, 375(9716):752-762 [viewed 25 June 2014] Available from: http://mail.elsevier-alerts.com/AEM/Clients/ELA001/2010/dilatedcardiomyopathy.pdf
  2. VORMBROCK J, LIEBETON J, WIRDEIER S, MEISSNER A, BUTZ T, TRAPPE HJ, PLEHN G. Determinants of Right Ventricular Muscle Mass in Idiopathic Dilated Cardiomyopathy: Impact of Left Ventricular Muscle Mass and Pulmonary Hypertension Int J Med Sci [online] , 11(8):834-840 [viewed 25 June 2014] Available from: doi:10.7150/ijms.6961
  3. BANSCH D.. Primary Prevention of Sudden Cardiac Death in Idiopathic Dilated Cardiomyopathy: The Cardiomyopathy Trial (CAT). [online] December, 105(12):1453-1458 [viewed 25 June 2014] Available from: doi:10.1161/​01.CIR.0000012350.99718.AD
  4. SCHRIER R. W.. Renal Volume, Renin-Angiotensin-Aldosterone System, Hypertension, and Left Ventricular Hypertrophy in Patients with Autosomal Dominant Polycystic Kidney Disease. Journal of the American Society of Nephrology [online] December, 20(9):1888-1893 [viewed 26 June 2014] Available from: doi:10.1681/ASN.2008080882
  5. NTUSI, Ntobeko B A et al. Clinical characteristics and outcomes of familial and idiopathic dilated cardiomyopathy in Cape Town: a comparative study of 120 cases followed up over 14 years. SAMJ, S. Afr. med. j. [online]. 2011, vol.101, n.6 [cited 2014-06-26], pp. 399-404 . Available from: . ISSN 0256-9574.
  6. The Jugular Venous Pressure and Pulse Contour. In: Walker HK, Hall WD, Hurst JW, editors. Clinical Methods: The History, Physical, and Laboratory Examinations. 3rd edition. Boston: Butterworths; 1990. Chapter 19. Available from: http://www.ncbi.nlm.nih.gov/books/NBK300/
  7. FITCHETT D H, SUGRUE D D, MACARTHUR C G, OAKLEY C M. Right ventricular dilated cardiomyopathy.. Heart [online] 1984 January, 51(1):25-29 [viewed 26 June 2014] Available from: doi:10.1136/hrt.51.1.25
  8. DZAU V. J., COLUCCI W. S., HOLLENBERG N. K., WILLIAMS G. H.. Relation of the renin-angiotensin-aldosterone system to clinical state in congestive heart failure. Circulation [online] 1981 March, 63(3):645-651 [viewed 26 June 2014] Available from: doi:10.1161/​01.CIR.63.3.645
  9. Karnath, B., & Thornton, W. (2002). Precordial and Carotid Pulse Palpation. Hospital Physician, 21.Chicago [viewed 26 June 2014] Available from: http://hpboardreview.com/pdf/hp_jul02_pulse.pdf
  10. BOLTWOOD C. M., TEI C., WONG M., SHAH P. M.. Quantitative echocardiography of the mitral complex in dilated cardiomyopathy: the mechanism of functional mitral regurgitation. Circulation [online] 1983 September, 68(3):498-508 [viewed 26 June 2014] Available from: doi:10.1161/​01.CIR.68.3.498

Differential Diagnoses

Fact Explanation
Acute coronary syndrome (ACS) [1] In ACS chest pain and sudden death can occur.[1]
Thiamine deficiency[2] Cardiac beriberi can manifest as heart failure. Echocardiographic features are similar to dilated cardiomyopathy [2]
Restrictive cardiomyopathy [3] Disease of the cardiac muscle that results to impaired filling of ventricles , with decreased or normal diastolic volume of one or both ventricles. Systolic function usually, at least early in the disease, remains normal and wall thickness may be normal or increased, depending on the underlying cause. [3]
Amphetamine toxicity [4] Palpitation,acute cardiac death can occur due ventricular arrhythmia. [4]
Cardiac temponade[5] In this disease ventricular filling is impaired and cardiac function is compromised and cause symptoms as dyspnea, tachycardia, and tachypnea.[5]
References
  1. FOX KEITH A.A., CLAYTON TIM C., DAMMAN PETER, POCOCK STUART J., DE WINTER ROBBERT J., TIJSSEN JAN G.P., LAGERQVIST BO, WALLENTIN LARS. Long-Term Outcome of a Routine Versus Selective Invasive Strategy in Patients With Non–ST-Segment Elevation Acute Coronary Syndrome. Journal of the American College of Cardiology [online] 2010 June, 55(22):2435-2445 [viewed 26 June 2014] Available from: doi:10.1016/j.jacc.2010.03.007
  2. LEE HS, LEE SA, SHIN HS, CHOI HM, KIM SJ, KIM HK, PARK YB. A Case of Cardiac Beriberi: A Forgotten but Memorable Disease Korean Circ J [online] 2013 Aug, 43(8):569-572 [viewed 26 June 2014] Available from: doi:10.4070/kcj.2013.43.8.569
  3. KUSHWAHA SUDHIR S., FALLON JOHN T., FUSTER VALENTIN. Restrictive Cardiomyopathy. N Engl J Med [online] 1997 January, 336(4):267-276 [viewed 19 June 2014] Available from: doi:10.1056/NEJM199701233360407
  4. KALANT H, KALANT OJ. Death in amphetamine users: causes and rates. Can Med Assoc J [online] 1975 Feb 8, 112(3):299-304 [viewed 26 June 2014] Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1956334
  5. REDDY P. S., CURTISS E. I., O'TOOLE J. D., SHAVER J. A.. Cardiac tamponade: hemodynamic observations in man. Circulation [online] 1978 August, 58(2):265-272 [viewed 26 June 2014] Available from: doi:10.1161/​01.CIR.58.2.265

Investigations - for Diagnosis

Fact Explanation
Echocardiography(Echo) [1] Left ventricular dilation and systolic dysfunction (depressed ejection fraction or shortening fraction), with or without mitral regurgitation can be identified by echo.It also helps to exclude other differential diagnosis. [1]
Electrcardiography (ECG) [1] By doing a ECG the following can be identified: sinus tachycardia, ST-T wave changes, Q waves, conduction disease, bundle-branch block, left ventricular hypertrophy, or ectopy, including supra-ventricular tachycardia, atrial fibrillation, or ventricular arrhythmia. [1],[2]
Chest radiography[1] CXR shows cardiomegaly and increased pulmonary vascular markings that are consistent with pulmonary oedema. [1]
Genetic testing[3] It is disease which can be transmitted as autosomal (dominant and recessive), X-linked, or mitochondrial traits. Therefore genetic testing useful in diagnosis [3].
Serological testing [1] To identify infective causes as viral, bacterial, fungal, parasitic, rickettsial, and spirotrichea infections[1]
References
  1. JEFFERIES JOHN LYNN, TOWBIN JEFFREY A. Dilated cardiomyopathy. The Lancet [online] 2010 February, 375(9716):752-762 [viewed 26 June 2014] Available from: http://mail.elsevier-alerts.com/AEM/Clients/ELA001/2010/dilatedcardiomyopathy.pdf
  2. Fei, L., Goldman, J. H., Prasad, K., Keeling, P. J., Reardon, K., Camm, A. J., & McKenna, W. J. (1996). QT dispersion and RR variations on 12-lead ECGs in patients with congestive heart failure secondary to idiopathic dilated cardiomyopathy. European heart journal, 17(2), 258-263. [viewed 26 June 2014] Available from: http://eurheartj.oxfordjournals.org/content/17/2/258.short
  3. SCHöNBERGER J, SEIDMAN CE. Many Roads Lead to a Broken Heart: The Genetics of Dilated Cardiomyopathy Am J Hum Genet [online] 2001 Aug, 69(2):249-260 [viewed 26 June 2014] Available from: doi:10.1086/321978

Investigations - Fitness for Management

Fact Explanation
Echocardiography [1] This is important to assess ejection fraction and cardiac function.[1]
Cardiac MRI[1] This is important in identifying cardiac fibrosis and to predict arrhythmias [1]
References
  1. JEFFERIES JOHN LYNN, TOWBIN JEFFREY A. Dilated cardiomyopathy. The Lancet [online] 2010 February, 375(9716):752-762 [viewed 25 June 2014] Available from: http://mail.elsevier-alerts.com/AEM/Clients/ELA001/2010/dilatedcardiomyopathy.pdf

Investigations - Followup

Fact Explanation
Echocardiography [1] This is important to evaluate the treatment by assessing cardiac function[1]
Biomarkers [1] Most widely used is BNP (B-type natriuretic peptide). It is used to monitor the presence and severity of fluid overload[1]
Histology [1] It is useful to distinguish between disease processes that need alternative treatment strategies and identify the cause for dilated cardiomyopathy, such as storage diseases, malignancies, sarcoidosis, and haemochromatosis , especially in secondary cardiomyopathies.[1]
References
  1. JEFFERIES JOHN LYNN, TOWBIN JEFFREY A. Dilated cardiomyopathy. The Lancet [online] 2010 February, 375(9716):752-762 [viewed 26 June 2014] Available from: http://mail.elsevier-alerts.com/AEM/Clients/ELA001/2010/dilatedcardiomyopathy.pdf

Investigations - Screening/Staging

Fact Explanation
Genetic testing [1] Screening evaluations for patients at risk for inheriting dilated cardiomyopathy has fostered early interventions that both reduce symptoms and decrease the morbidity and mortality associated with arrhythmias or thromboembolic events.[1]
References
  1. SCHöNBERGER J, SEIDMAN CE. Many Roads Lead to a Broken Heart: The Genetics of Dilated Cardiomyopathy Am J Hum Genet [online] 2001 Aug, 69(2):249-260 [viewed 26 June 2014] Available from: doi:10.1086/321978

Management - General Measures

Fact Explanation
Blood pressure control[1] This can be achieved by controlling salt intake and prescribing appropriate anti hypertensives. [1] ,[2]
Management of thyroid disorders [3] There are 3 frequently used therapies: antithyroid medications, thyroidectomy, and radioactive Iodine treatment. According to the patient's status management may differ.[3]
Control alcohol consumption [4] With reduction of alcohol consumption oxidative stress caused by alcohol is reduced.[4]
Anemia management [5] Anemia can be managed with dietary modification and other medical management such as iron supplementation and erythropoietin. [5]
References
  1. JEFFERIES JOHN LYNN, TOWBIN JEFFREY A. Dilated cardiomyopathy. The Lancet [online] 2010 February, 375(9716):752-762 [viewed 26 June 2014] Available from: http://mail.elsevier-alerts.com/AEM/Clients/ELA001/2010/dilatedcardiomyopathy.pdf
  2. ENGELMEIER R. S., O'CONNELL J. B., WALSH R., RAD N., SCANLON P. J., GUNNAR R. M.. Improvement in symptoms and exercise tolerance by metoprolol in patients with dilated cardiomyopathy: a double-blind, randomized, placebo-controlled trial. Circulation [online] 1985 September, 72(3):536-546 [viewed 26 June 2014] Available from: doi:10.1161/​01.CIR.72.3.536
  3. Iagaru, A., & McDougall, I. R. (2007). Treatment of thyrotoxicosis. Journal of nuclear medicine, 48(3), 379-389. [viewed 26 June 2014] Available from: http://jnm.snmjournals.org/content/48/3/379.short
  4. LUCAS DIANE L., BROWN RICARDO A., WASSEF MOMTAZ, GILES THOMAS D.. Alcohol and the Cardiovascular System. Journal of the American College of Cardiology [online] 2005 June, 45(12):1916-1924 [viewed 26 June 2014] Available from: doi:10.1016/j.jacc.2005.02.075
  5. SILVERBERG DONALD S., WEXLER DOV, IAINA ADRIAN. The importance of anemia and its correction in the management of severe congestive heart failure. European Journal of Heart Failure [online] December, 4(6):681-686 [viewed 26 June 2014] Available from: doi:10.1016/S1388-9842(02)00115-0

Management - Specific Treatments

Fact Explanation
Medical management [1] Medical therapy remains the mainstay of treatment in patients with dilated cardiomyopathy and heart failure. Inhibition of angiotensin - converting enzymes and β-blockade with or without diuretics continue to be standard options. [1]
Use of implantable cardioverter- defibrillators [1] For patients with left ventricular ejection fraction of <30% and symptomatic heart failure for which they are receiving optimum medical therapy are indicated for this. [1]
Cardiac resynchronisation[1] Use in patients with advanced heart failure and ventricular conduction delay. This therapy is designed to eliminate the delay in activation of the left ventricular free wall, a finding often seen in adults with left ventricular systolic dysfunction.[1]
Surgical management[1] The goal is to improve the biophysics of the left ventricle and reduce the stimulus for unfavorable remodeling. - The Batista procedure, or partial left ventriculectomy, is used in patients with end stage dilated cardiomyopathy. - Surgical ventricular restoration by recreation of the elliptical shape of the left ventricle by volume reduction with a sizing balloon.[1],[2]
cardiac transplant[1] Important in extreme cases. Waiting times for organs remain a significant restriction
Stem cell therapy [1] Used in end stage cases but still of questionable value.[1],[3]
References
  1. JEFFERIES JOHN LYNN, TOWBIN JEFFREY A. Dilated cardiomyopathy. The Lancet [online] 2010 February, 375(9716):752-762 [viewed 26 June 2014] Available from: http://mail.elsevier-alerts.com/AEM/Clients/ELA001/2010/dilatedcardiomyopathy.pdf
  2. DREYFUS G, MIHEALAINU S. The Batista procedure Heart [online] 2001 Jan, 85(1):1-2 [viewed 26 June 2014] Available from: doi:10.1136/heart.85.1.1
  3. GNECCHI M., ZHANG Z., NI A., DZAU V. J.. Paracrine Mechanisms in Adult Stem Cell Signaling and Therapy. Circulation Research [online] 2008 November, 103(11):1204-1219 [viewed 26 June 2014] Available from: doi:10.1161/​CIRCRESAHA.108.176826