Cardiology Notes 4

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  The criteria for ICD insertion are: 1) patients with LVEF <40% with non sustained VT 2) patients with sustained VT 3) patients who have had any VT or VF leading to cardiac arrest 4) cardiomyopathy and ventricular arrhythmias 5) patients with previous MI and ejection fraction <30%

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  PROLONGED QT  A QT interval of >0.45 is prolonged.

DRUGS causing PROLONGED QT tricyclic antidepressants (eg. amitryptiline) , quinidine, erythromycin, amiodarone, phenothiazines (chlorpropramide), antihistamines (terfenadine) grapefruit juice, sotalol

METABOLIC causes Hypokalaemia, Hypocalcaemia, Hypomagnesaemia, Hypothermia, Hypothyroidism

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  Complete Ht block: maternal SLE, Lev’s disease, Lenegre’s disease, Endocarditis, Lyme disease, Chagas’ disease and Drugs,
  
  WPW not use verapamil and digoxin

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  Second degree heart block, Mobitz type I (Wenkebach) is due to progressive prolongation of PR interval and then missing a beat>> benign. Mobitz type II second degree heart block with sudden dropped QRS >> infranodal block and need pacing, Also 2nd HB can occur with 2:1 (only 1 QRS is conducted for 2 p waves) or 3:1.

Second-degree heart block in anterior myocardial infarction, second is associated with a high risk of progression to complete heart block, and temporary pacing followed by permanent pacemaker implantation is usually indicated.(kumar).

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  Burgada syndrome: adult sudden death D2 VF, south East Asia.

ECG: RBBB + ST elevation in V1-V3. ttt only ICD

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  Digoxin toxicity can occur especially with renal impairment. It typically causes nausea & vomiting. ST depression occurs along with bradycardia on the ECG. The patient may also get xanthopsia (yellow vision)