Prinzmetals angina

DHPs are potent arterial vasodilators. They act on resistance vessels and therefore reduce peripheral vascular resistance, lower arterial blood pressure, and antagonize vasospasms in coronary or peripheral arteries. By reducing afterload, DHPs also reduce cardiac oxygen demand. Together with their vascular spasmolytic effect, this explains most of the beneficial actions of DHPs in angina pectoris. Most DHPs are only licensed for the therapy of hypertension, some of them also for the treatment of angina pectoris and vasospastic (Prinzmetal) angina. 

Patients with variant or Prinzmetal angina secondary to coronary spasm are more likely to experience pain at rest and in the early morning hours. Pain is not usually brought on by exertion or emotional stress nor is it relieved by rest the electrocardiogram (ECG) pattern is that of current injury with ST-segment elevation rather than depression. 

Good candidates for calcium channel antagonists include patients with contraindications or intolerance to /3-blockers, coexisting conduction system disease (excluding the use of verapamil and possibly diltiazem), Prinzmetal angina, peripheral vascular disease, severe ventricular dysfunction, and concurrent hypertension. Amlodipine is probably the agent of choice in severe ventricular dysfunction, and the other dihydropyridines should be used with caution if the EF is less than 40%. 

Carboline derivatives, (IV) and (V), prepared by Sawyer (6) and the author (7), respectively, were effective as PDE5 inhibitors and used in the treatment of variant (Prinzmetal) angina and hypertension. 

Q13 Calcium channel blockers decrease the opening of L-type calcium channels in the plasma membrane of vascular smooth muscle cells, and so reduce intracellular calcium concentration and contractile activity. The blood vessels therefore dilate. Calcium channel blockers act mainly on the arterial side of the circulation, and the dihydropyridines, such as nifedipine, are useful coronary arteriolar dilator agents. These agents are usually the treatment of choice for Prinzmetal angina. 

The principal forms relevant to choice of drug therapy are angina of exercise (commonest) and its worsening form, unstable (preinfarction or crescendo) angina (see below), which occurs at rest. Variant (Prinzmetal) angina (very uncommon) results from spasm of a large coronary artery. 

Prinzmetal angina with electrocardiographic changes has been seen 10 minutes after a dose of iodipamide (SEDA-2,373). In another case an anaphylactoid reaction after left ventriculography was associated with electrocardiographic changes apparently due to coronary artery spasm (63). 

First predominant subendocardial compromise occurs and then, transmural and homogeneous compromise ACS with ST-segment elevation evolving to Q-wave infarction or coronary spasm (Prinzmetal angina) ... 

Figure 3.8 Morphologies of taller than normal T wave in patients with ischaemic heart disease. (A) T wave very tall not preceded by rectified ST segment This morphology is frequently observed in a transitory form in case of Prinzmetal angina (Figure 8.44). (B) A tall T wave, very symmetric and with previous rectified ST segment completely abnormal for V2 lead, which may be frequently observed in a hyperacute phase of an ACS with ST-segment...

Transient Q waves in the course of an acute disease. Sometimes in the course of typical ACS a generally transient Q wave appears. This results in the clinical setting of aborted MI and also happened in the coronary spasm (Prinzmetal angina) (atypical ACS). As has already been commented on... 

Figure 8.10 Patient with crises of Prinzmetal angina, who presented during these crises typical of subepicardial injury pattern. During the remission of pain (Holter method recording) the injury pattern disappeared within a few seconds.

Figure 8.11 Holter recording of a patient with a severe crisis of Prinzmetal angina. Observe the presence of clear ST-segment and TQ alternance together with some PVC.

Figure 8.46 Above Crisis of coronary spasm (Prinzmetal angina) recorded by Holter ECG. (A) Control. (B) Initial pattern of a very tall T wave (subendocardial ischaemia). (C) Huge pattern of ST-segment elevation. (D-F) Resolution towards normal values. Total duration of the crisis was 2 minutes. Below Sequence of a crisis of Prinzmetal angina with the appearance of ventricular tachycardia runs at the moment of maximum ST-segment elevation.

Figure 11.2 Trend of heart rate and ST-segment deviations crisis. In case of Prinzmetal angina (B) the heart rate does...

Bayes de Luna A, Carreras F, Cladellas M, Oca F, Sagues F, Garcia Moll M. Holter ECG study of the electrocardiographic phenomena in Prinzmetal angina attacks with emphasis on the study of ventricular arrhythmias. J Electrocardiol 1985 18 267. 

Acute Myocardial Infarction (MI) Acute Pericarditis High take off Brugada syndrome Left ventricular aneurysm Prinzmetals angina... 

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