Cardiac Conduction System Affection in a Case of Swine Flu

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tolerability of oseltamivir suspension in patients on haemodialysis and continuous ambulatory peritoneal dialysis. Nephrol Dial Transplant (2006) 21:2556–2562. 8.

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Cardiac Conduction System Affection in a Case of Swine Flu RK Gokhroo*, HD Barjatya**, K Bhawna***

Abstract We present a case of swine flu presenting as bilateral pneumonia with involvement of cardiac conduction system in the form of increased PR interval and sinus bradycardia during the initial course of disease process. To the best of our knowledge, affection of conducting system in a case of swine flu has not been reported in the literature so far.

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Introduction

the time of admission, Hb=12.3gm%, TLC=4300 cells/mm3, polymorphs were 83%, ESR=50mm of 1st Hour , Blood sugar = 61.0 mg/dl, blood urea=182.0 mg/dl, S.creatinine=1.6mg/dl, CPK-MB=27.7 IU/L, S.Sodium = 138.8 meq/dl, S.Potassium=5.1 meq/dl, S.calcium=8.9 meq/dl, SPO2=81% ,LFT was normal, pH=7.14 with respiratory and metabolic acidosis in arterial blood gas analysis. Chest Skiagram showed bilateral heterogenous infiltration in lower zones with cardiothoracic ratio of 0.6. Echocardiography showed left ventricle hypertrophy with no other abnormality. Initially patient was treated as a case of left ventricular failure but patient did not respond to decongestive therapy and had persistent low arterial oxygen saturation. On the basis of disproportionate and persistent signs and symptoms, diagnosis of bilateral bronchopneumonia had been considered. Patient was taken on mechanical ventilation due to low oxygen saturation and deteriorating clinical status. On third day of admission, repeat investigations showed Na+ S.Sodium =145.0 meq/l, S.Potassium =4.9 meq /l, SPO2= 94%, pH=7.30, blood urea=15.0 mg/dl, S. creatinine= 1.0 mg/dl, CPK-MB=3.0. Electrolytes were within normal limits during the further course of the disease . Electrocardiogram (Fig.Ia) on day 1 showed HR=88/min, regular, normal axis, LVH, T in lead I and aVL, on day 3rd electrocardiograph (Fig.1b) showed HR=90/min, regular and PR interval=0.28 sec. on day 4th electrocardiograph(Fig.1c) showed severe sinus bradycardia with heart rate of 36/min, PR interval was 0.28 sec, QTc=.49 sec, and QRS duration was 0.12 sec. Thus, patient had involvement of cardiac conduction tissue involvement on the 3rd, 4th and subsequent days of disease course. Patient died on 9th day.

ardiac conduction system involving SA node and AV node has been found to be affected by various systemic disorders including infections(Viral myocarditis, endocarditis, Lyme disease, Chagas disease, Diphtheria, tuberculosis, syphilis, rheumatic fever etc.), infiltrative(Amyloidosis, haemochromatosis, sarcoidosis), collagen vascular disorders, drug toxicity and post cardiac surgery. Affection of conducting system and myocarditis by various viral disorders in not a rare entity. This has been reported in coxasackie virus, EBV virus, adenovirus, hepatitis C, HIV etc. Influenza A infection is a debilitating respiratory illness rarely affecting the Cardiovascular system. Influenza A and B viruses are enveloped viruses with a segmented genome made up of eight single-standard RNA segments of 890 to 2341 nucleotides each.1 Influenza A is further subdivided into 16 hemagglutinin (H1 to H16)and nine neuraminidase(N1 to N9)subtypes on the basis of the antigenicity of the surface proteins hemagglutinin and neuraminidase. Cardiac involvement has been reported in cases of swine flu.2,3 Epidemiological studies have demonstrated an association between influenza epidemics and cardiovascular mortality.

Case Report A patient, 42 years old male, presented in the department of cardiology as a case of accelerated hypertension with shortness of breath and low grade fever for three days. Patient had past history of hypertension with no documents available. There was no history of tuberculosis, diabetes or any other significant illness. At the time of admission, patient was conscious, oriented. His vital signs revealed pulse = 102/min regular, blood pressure = 220/120 mmHg, respiratory rate = 34/ min with mild cyanosis. Jugular venous pressure was normal. Respiratory system examination revealed bilateral coarse crepts and rhonchi. Other system was normal except the presence of soft left ventricular third heart sound on cardiac auscultation. On investigations, sputum was positive for H1N1 virus. At

Discussion We have reported a case of swine flu presenting as bilaterial lobar pneumonia with involvement of cardiac conduction system. In our case, PR interval was normal during first three days of onset of symptoms. On 4th day, we found an increase in PR interval (0.28 s) with deterioration in patient’s clinical status with refractory hypotension not responding to vasopressors. On 7th day, patient developed sinus bradycardia with heart rate of 36/min, PR interval of 0.28 sec. Initially patient had hypoxia, increased blood urea, normal electrolytes and respiratory and metabolic acidosis, which improved with treatment. The temporal sequence of increase in PR interval and sinus bradycardia after 3- days of onset of symptoms is suggestive of progressive increase in involvement of conducting tissue and

*Professor & Head, Department of Cardiology, **Professor & Unit Head, Department of Medicine, J.L.N. Medical College, Ajmer, ***Post Graduate Resident, Department of Medicine, J.L.N. Medical College, Ajmer Received: 11.03.2010; Revised: 17.09.2010; Accepted: 18.09.2010 © JAPI • january 2011 • VOL. 59



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severe form of myocarditis than previously encountered influenza strains.5 Fulminant myocarditis caused by a viral infection in uncommon and influenza A virus associated fulminant myocarditis is “extremely rare with only a few cases reported in the literature”. Patients with fulminant myocarditis can present with fatal arrhythmias, atrioventricular blocks and or varying degree of cardiogenic shock. The exact potential mechanism for conduction tissue abnormalities remains to be postulated. Whether it is due to inflammatory edema pressing the AV node and other conduction tissue or primarily directly affecting this conduction tissue/AV nodal pacemaker cells resulting into resting membrane potential changes to explain conduction abnormality remains to be verified.5-7 Relative bradycardia has been reported in various viral hemorrhagic fevers but affection of conduction tissue involvement has not been demonstrated, through postulated to be caused as a result of either a part of myocarditis or immune related.5-8

References Fig. 1 : (a) Normal rate and rhythm, LVH, T in 1st and aVL. (b) Normal rate and rhythm, PR interval = 0.28 sec. (c) Sinus bradycardia with heart rate of 36/min, PR interval=0.28 sec.

severity of disease, culminating into a fatal outcome. It suggests that in the terminal phase, SA node and AV node affection was preferentially more than the inter nodal connecting pathways, bundle branch or Purkinje fibres. It may be a rare manifestation. In our experience, at our institute till now, we had 27 confirmed cases of swine flu, and among those, only one patient had conducting system involvement. A total of 9 cases of influenza myocarditis were diagnosed during the winter epidemic of influenza 1998-1999.4 But exact incidence and predisposition of influenza virus to cardiac conducting system without myocarditis has not been reported in the literature so far.

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Noda T, Sagara H, Yen A et al. Architecture of ribonucleoprotein complexes in influenza A virus particles. Nature 2006;439:490-92.

2.

Seneca H.Influenza:Epidemiology, etiology, immunization and management. J Am Geriatr Soc 1980;28,241-45.

3.

Mamas MA, Fraser D, Neyses L. Cardiovascular manifestations associated with influenza virus infection. Jnt J Cardiol 2008;130:30449.

4.

Onitsuka H, Imamura T, Miyamoto N, Shibata y, Kashiwage T et al. Clinical manifestations of influenza a myocarditis during the influenza epidemic of winter 1998-1999. J Cardiol 2001;37:315-23.

5.

Bratincsak A, EL-Said hG, Bradley jS, et al. Fulminant myocarditis associated with pandemic H1N1 influenza virus in children. J Am Coll Cardiol 2010;DOI:10.10.16/j.jacc.2010.01.004

6.

Ostergaard L, Huniche B, Andersen PL. Relative bradycardia in infectious diseases. J Infect 1996;33:185-91.

7.

Cunha BA. The diagnostic significance of relative bradycardia in infectious disease. Clin Microbiol Infect 2000;6:633-4.

8.

Fink J, GuF, Vasudevan SG. Role of T cells, cytokines and antibody in dengue fever and dengue haemorrhagic fever. Rev Med Virol 2006;16:263-75.

Bratiniscsak. A et al has raised the possibility of associated

Influenza A (H3N2) Associated Acute Necrotising Encephalopathy SA Sangle1, Girish Vadgaonkar2, DB Kadam3, Manjeet Chadha4 Abstract We present a case of 16 year old female admitted with complaints of influenza like symptoms followed by convulsions and sudden impairment of consciousness. Magnetic resonance imaging abnormalities were found in bilateral thalami including cerebellum. Diagnosis of influenza associated acute necrotizing encephalopathy was made on the basis of clinical features, neuroimaging findings and isolation of influenza A(H3N2) virus from throat swab. This is probably first case of Influenza associated acute necrotizing encephalopathy reported in India in 2009. Associate professor, 2Resident, 3Professor, Dept. of Medicine, B.J.Medical College and Sassoon General Hospitals, Pune; 4Deputy Director National Institute of Virology, Pune. Received: 23.03.2010; Accepted: 25.04.2010 1

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nfluenza virus associated encephalopathy is a disease of young children. It has mostly been reported from Japan and Taiwan, but cases have been reported from Europe and North © JAPI • january 2011 • VOL. 59