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Paper text:
variant angina commonly manifests as chest pain and transient st elevation by coronary spasm , and generally follows a benign clinical course.1 ) rarely , syncope induced by ventricular arrhythmia associated with transient myocardial ischemia can be developed by coronary spasm.2)3 ) if the cause of syncope is not correctly diagnosed , patients are at risk of recurrent syncope.4 ) in particular , syncope without chest pain is an uncommon manifestation of variant angina .
thus , as in this case , it can be missed as the cause of syncope .
a 68-year - old man visited our emergency room due to recurrent syncope . he had experienced four episodes of syncope with dizziness and chest discomfort during the prior 2 months .
the episodes were evoked when he was preparing his boat for sailing in early morning . on admission ,
vital signs showed blood pressure ( bp ) of 120/80 mmhg , pulse rate of 60 beats / min , respiratory rate of 20 breaths / min and body temperature of 36.5. he had a 10-year history of diabetes mellitus with application of oral hypoglycemic agents .
the initial electrocardiogram ( ecg ) showed sinus rhythm with t inversion in the v5 and v6 leads .
transthoracic echocardiogram revealed left ventricular hypertrophy , mildly decreased ejection fraction , and hypokinetic left ventricular wall motion .
twenty four hour holter monitoring showed normal sinus rhythm and infrequent premature ventricular complexes ( pvcs ) .
coronary angiography revealed 70% stenosis at proximal left anterior descending artery ( lad ) ( fig .
after 4 days , he was readmitted because of severe dizziness and we performed 48-hour holter monitoring . during his second admission , syncope occurred for about 3 minutes .
the holter monitoring during the syncope episode revealed st - segment elevation followed by pvcs ( fig .
we suspected that the ventricular arrhythmia resulted from transient myocardial ischemia by variant angina , because stsegment elevation was seen before vt and syncope occurred in the morning .
in contrast , after intracoronary ergonovine injection , nearly total occlusion of lad developed ( fig .
there was no chest pain and no change of bp or ecg during the provocation test .
we speculate that it may have caused no changes of ecg during the provocation test .
the patient was discharged with medications including calcium channel blockers . at present , he has been regularly followed in the outpatient clinic without symptoms .
variant angina was first described a specific entity of angina pectoris characterized by angina pain occurring at rest and associated with st - segment.1 ) variant angina generally has a good prognosis ; the 10-year survival rate is over 80% .
however , variant angina patients with severe coronary artery disease have poor prognosis.4 ) rarely , vasospasm - induced ischemia causes life - threatening ventricular arrhythmia , syncope , and sudden cardiac death.5 ) syncope associated with vt can be caused by myocardial ischemia due to severe coronary artery stenosis in ischemic heart disease.6 ) in the present case , since the patient had no chest pain or evidence of ischemic heart disease on routine workup , we presumed that he had no significant coronary lesion that could cause ischemia that would lead to ventricular arrhythmia .
however , the patient had coronary spasm , which can cause transient myocardial ischemia leading to lethal arrhythmia and syncope .
the frequency of variant angina presenting as syncope is not uncommon , but only a few cases of variant angina without chest pain were reported.2)3)789 ) holter monitoring of the patient revealed st - segment elevation followed by vt during syncope indicating that the probable cause of syncope was variant angina .
after the syncope episode , we reanalyzed the previous 24-hour holter monitoring that was performed during the first admission , and observed that st - segment elevation was present before pvc development .
if we had recognized abnormal st - segment elevation on the first holter monitoring and suspected variant angina , we could have avoided the re - development of syncope .
total occlusion of lad developed during ergonovine injection , however , we did not identify the st elevation and polymorphic vt during the provocation test .
polymorphic vt in holter monitoring might develop only in prolonged coronary vasospasm . a reported case of variant angina showing polymorphic vt with resting chest pain
was not associated with st elevation during ergonovine provocation test10 ) is similar to our case .
the main therapy for variant angina is medical treatment using nitrate and calcium channel blockers .
additional coronary intervention in variant angina patients with fixed coronary stenosis is controversial . in one study , coronary spasm after pci was induced in 76.7% of cases in follow - up provocation testing.11 ) the results suggest that medical therapy with calcium channel blockers is important and should be continued regardless of whether pci was performed or not .
coronary intervention is helpful in patients with discrete proximal fixed stenosis , and it may be indicated in patients refractory to optimal pharmacologic management.12 ) vt can disappear upon revasularization.13 ) in patients with recurrent life - threatening ventricular arrhythmia in spite of maximal medical treatment , implantable cardioverter defibrillator insertion can be indicated.14 ) for our case , we performed coronary stenting in the patient , because severe eccentric plaques were shown on intravascular ultrasonography and uncontrolled ventricular arrhythmia occurred even on medications .
after coronary stenting , the previous symptoms and ventricular arrhythmia were not represented in the patient .
thus , we suggest that coronary stenting along with optimal medical therapy may be the most appropriate option in variant angina with severe fixed lesion in proximal coronary artery .
we missed the diagnosis of variant angina during the first admission because the patient did not complain of chest pain and we did not identify abnormal st - segment elevation . thus , syncopal patient of variant angina without typical chest pain may be misdiagnosed as in our case . therefore , in the event of an unexplained syncope , it is important to interpret holter monitoring carefully and to consider coronary spasm provocation test for the diagnosis of variant angina , if clinically indicated .
a 68-year - old man was admitted for a syncope workup . after routine evaluation , he was diagnosed with syncope of an unknown cause and 
 was discharged from the hospital . 
 he was readmitted due to dizziness . on repeated holter monitoring , 
 polymorphic ventricular tachycardia was detected during syncope . 
 we performed intracoronary ergonovine provocation test ; severe coronary spasm was induced at 70% stenosis of the proximal left anterior descending artery . 
 the patient was treated with percutaneous coronary intervention . 
 we present a rare case of syncope induced by ventricular arrhythmia in a patient with variant angina without chest pain .