A case of bronchospasm-induced takotsubo cardiomyopathy during adenosine stress testing

Excerpt

Our patient is a 72-year-old female with a history of well-controlled asthma who underwent an adenosine single-photon emission computerized tomography (SPECT) myocardial perfusion imaging (MPI) stress test an outpatient cardiology office as part of a preoperative evaluation for a left hip replacement after she was found to have anterolateral T-wave inversions on preoperative electrocardiogram (ECG). The patient had no wheezing or upper respiratory symptoms on the day of the exam and she was pre-treated with her home albuterol inhaler before initiation of the study. A same-day rest-stress protocol was used during the study, utilizing adenosine as the pharmacologic agent and Tc-99m sestamibi as the tracer per protocol. Adenosine, at a dose of 31 mg was given intravenously over 4 minutes without adjunctive exercise. Within 2 minutes of the adenosine infusion completing, the patient developed respiratory distress, which became severe. Albuterol was administered however she continued to have severe wheezing and bronchospasm. Her pulse oximetry saturation dropped to 81%. Aminophylline was given quickly at a dose of 150 mg intravenously and 6 liters of oxygen were administered by nasal cannula, which failed to raise her pulse oximetry saturation. Epinephrine 0.5 mg was given intramuscularly and positive pressure ventilation with bag valve mask was initiated. Her saturation rose to 90%, she was stabilized and was transferred to the hospital via emergency medical services. By the time she was evaluated in the Emergency Department, she was breathing comfortably and feeling nearly back to her baseline. An ECG (Figure 1) was performed in the Emergency Department, which showed sinus rhythm with no new ischemic changes. Her troponin on presentation was undetectable. She received an ipratropium-albuterol nebulizer treatment and was subsequently discharged in stable condition. Upon being discharged from the Emergency Department she returned to the Cardiology office to complete the post-adenosine SPECT MPI part of the stress test when she began experiencing sudden onset of squeezing chest pain that radiated to her jaw, along with diaphoresis. Her blood pressure at the time was 100/60 mmHg and her heart rate was 80 beats per minute. She was taken back to the Emergency Department where a second ECG (Figure 1) was performed and demonstrated interval development of 2 mm ST-segment elevations in the anterolateral precordial leads. She was referred for emergent cardiac catheterization, which demonstrated non-obstructive coronary artery disease (Figure 2). Ventriculography revealed a hyperdynamic base with apical ballooning consistent with takotsubo cardiomyopathy. These findings were also seen on transthoracic echocardiogram (Figure 3). A left ventricle to aorta pull-back with a pigtail catheter demonstrated significant left ventricle outflow tract obstruction with gradient of 72 mmHg (Figure 4). A recent follow-up echocardiogram six months post event has shown complete resolution of the cardiomyopathy.

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