Normal Hearts with Abnormal Beats Introduction

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Normal Hearts with Abnormal Beats
Devna Mangrola, MD, Nicholas Wettersten, MD; Yingbo Yang , MD
University of California, Davis Medical Center; Sacramento, CA
Investigational Studies
Introduction
•Idiopathic ventricular tachycardia (IVT) refers only to VT in
structurally normal hearts. It is identified only after a thorough
cardiac work up including:
• resting ECG
• assessment of ventricular function
• Exclusion of ischemia (2,3)
Ventricular Tachycardias (VT) are often seen in structurally
abnormal hearts but 10% of VT’s are seen in patients with no
apparent structural heart disease and are termed idiopathic
ventricular tachycardias (IVT). (1) The treatment and prognosis
of IVT differs from VT associated with structural heart disease.
Learning Objectives
•
•
•
to consider IVT in patients presenting with VT without any
apparent structural heart disease
to understand the thorough evaluation that must take
place to diagnose IVT
to recognize the treatment options available for patients
with symptomatic IVT
ECG at presentation shows wide complex tachycardia with right bundle
branch block and left anterior fascicular block
History
Medications
• metformin 500mg PO BID
Past Medical History
• Type 2 Diabetes Mellitus
• Hyperlipidemia
Family History
• non-contributory
Social History
• born in Mexico
• smokes 1 cigarette every 2 months for years
• no illicit drug use
Physical Exam
Blood pressure: 93/58 Heart Rate: 190
General: Patient was in moderate distress with normal
mentation
Cardiac exam: tachycardic heart rate with regular rhythm
without any appreciable gallops or murmur, no jugular venous
distension or peripheral edema
Neurological exam: CN II-XII intact without motor or sensory
deficit
•IVT can be classified into subgroups according to location:
• Ventricular outflow tracts
• Fascicles
• Papillary muscles
• Epicardial surfaces
•Posterior Fascicular VT, also known as Verapamil Sensitive VT, has
the common triad of features of:
• Induction with atrial pacing
• RBBB morphology with left axis deviation
• Occurrence in patients without structural heart
disease (4)
Case Presentation
• A 62 year old woman presented to the Emergency
Department (ED) with palpitations and chest pain that
awoke her from sleep.
• She rated the chest pain as 10/10 in severity with radiation
to her jaw. It was accompanied by dyspnea, diaphoresis,
nausea, and weakness.
• Her palpitations were constant lasting for 6 hours without
any alleviating or aggravating factors.
• She described having intermittent palpitations with no
associated chest pain over the past 6-7 months.
• Ten years prior, she had a similar episode of palpitations
during which she was given IV medication but could not
recall the name of the drug.
Discussion
•Rarely can IVT cause sudden cardiac death or syncope. (5)
ECG showing fusion beats (red circles) that are diagnostic of ventricular
tachycardia
•In rare cases where patients have persistent tachycardia,
tachycardia related cardiomyopathies can occur (6)
•In patients with significant symptoms or who are resistant to
medical therapy, radiofrequency ablation can be considered. In a
large percentage of cases (>80%) catheter ablation leads to long
term success with rare complications. (7)
ECG of same patient in normal sinus rhythm after IV verapamil administration
• This case highlights the need to consider idiopathic ventricular
tachycardia in patients with VT and structurally normal hearts as
management, prognosis, and treatment differs from other VTs
Additional Studies:
Troponin: Reference range (<0.04 ng/ml) : 0.26 (0hr), 2.39 (6 hr), 4.27 (12 hr), 4.16 (18 hr)
Echocardiogram (in VT): Left ventricular function reduced with estimated ejection fraction of 25-30%, normal
right ventricular size, normal systolic function of right ventricle, mild regurgitation of pulmonic, tricuspid, and
mitral valve.
Echocardiogram (in sinus): left ventricular diastolic and systolic function. The ejection fraction is 55-60%. Normal
right ventricular size and systolic function.
Cardiac catheterization: mild CAD with 40% calcified plaque in proximal mid LAD, normal left and right heart
pressures, normal left ventricular size, wall motion, systolic function and cardiac output.
Hospital Course
• Patient was sedated and cardioverted with 200J twice, however the arrhythmia persisted.
• Subsequently, she was started on an amiodarone drip which transiently slowed the HR to the 140’s but with
persistence of the wide complex rhythm.
• She also received a trial of adenosine and metoprolol without any effect.
• Idiopathic verapamil sensitive VT was considered and 2.5mg IV verapamil was given with conversion to
normal sinus rhythm.
• She was then taken for electrophysiologic study and found to have fascicular ventricular tachycardia and
underwent ablation.
• The ablation procedure was complicated by biventricular laceration and liver lacerations leading to
pericardial tamponade and cardiogenic shock.
• The patient required exploratory sternotomy for repair of biventricular lacerations and exploratory
laparatomy for liver laceration repair. After being stabilized in the ICU, the patient was discharged with no
further incidents of VT.
References
1) Lerman BB, Stein KM,Markowitz SM.Mechanism of idiopathic ventricular tachycardia. J
Cardiovasc Electrophysioly.1997;8:571–583
2) Prystowsky EN, Padanilam BJ, Joshi S, Fogel RI. Ventricular Arrhythmias in the Absence of
Structual Heart Disease. J Am Coll Cardiol. 2012 May 15;59(20):1733-44.
3) Latif S, Dixit S, Callans DJ. Ventricular arrhythmias in normal hearts. Cardiol Clin. 2008
Aug;26(3):367-80
4) Nogami A. Idiopathic left ventricular tachycardia: assessment and treatment. Card
Electrophysiol Rev. 2002 Dec;6(4):448-57.
5) Ohe T, Aihara N, Kamakura S, Kurita T, Shimizu W, Shimomura K. Long-term outcome of
verapamil-sensitive sustained left ventricular tachycardia in patients without structural heart
disease. J Am Coll Cardiol 1995;25:54–58.
6) Hasdemir C, Ulucan C, Yavuzgil O, Yuksel A, Kartal Y, Simsek E, Musayev O, Kayikcioglu M,
Payzin S, Kultursay H, Aydin M, Can LH. Tachycardia-induced cardiomyopathy in patients with
idiopathic ventricular arrhythmias: the incidence, clinical and electrophysiologic characteristics,
and the predictors.J Cardiovasc Electrophysiol. 2011 Jun;22(6)
7) Lin D, Hsia HH, Gerstenfeld EP, Dixit S, Callans DJ, Nayak H, Russo A, Marchlinski FE. Idiopathic
fascicular left ventricular tachycardia: linear ablation lesion strategy for noninducible or
nonsustained tachycardia. Heart Rhythm. 2005 Sep;2(9):934-9.
Acknowledgements
Thanks to Dr. Yang and Dr. Wettersten for their help in putting together this
case study.
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