Arrhythmias: amiodarone caused pulmonary toxicity.

Clinical bottom line (level 4)

Around 6% of patients on high doses of amiodarone developed pulmonary toxicity.

Dusman et al: Circulation 1990; 82 (1): 51-59

Expires November 2003

The study

Case series with objective outcomes, not adjusted for confounding factors, not validated in an independent set of patients.

Setting: university medical centre, USA

573 patients (aged range 5 to 88 years; mean 58, 79% male) 80% with VT or VF, remainder with SVT

Excluded if

heart failure, infection or malignancy

Treated with amiodarone for > 3 days. Patients initially received 800 mg/day loading dose for 6-8 weeks, then later 1600 mg/day for one week, followed by 800 mg/day for one month. Maintenance therapy dose ranged from 50 to 800 mg/day.

100% followed for at least 2 years
Outcomes studied:

pulmonary toxicity diagnosed by 2 or more of: new onset of pulmonary symptoms (dyspnoea, cough or pleuritic chest pain); new chest radiographic abnormality such as interstitial or alveolar infiltrate; decrease in DLCO of 20% from pretreatment value (or < 80% predicted); abnormal lung uptake from gallium-67 radioisotope; characteristic histologic changes from bronchoscopy and lung biopsy samples.

The evidence

outcome	time to outcome	number of patients/total number	% (95% CI)
pulmonary toxicity	at least 2 years	33/573	5.8% (3.9% to 7.7%)

Three patients with pulmonary toxicity died (all within a month of diagnosis).
No toxicity was seen in patients younger than 40 years old.

Comments

Inconsistent use of BAL may skew results.
Patients were on higher doses than currently used.

Citation

Dusman RE, Stanton MS, Miles WM, et al: Clinical features of amiodarone-induced pulmonary toxicity. Circulation 1990; 82 (1): 51-59

Contributor: Chris Ball and Clare Wotton, November 2000
Reviewer: William Rhoton

_{Clinical Question.}

_Patient	_arrhythmias
_{Intervention or Exposure}	_amiodarone
_Outcome	_{pulmonary toxicity}