Pharmacological spasm provocation testing in 2500 patients: provoked spasm incidence, complications and cardiac events.

Pharmacological spasm provocation tests such as acetylcholine (ACh) and ergonovine (ER) had been performed in the clinic. We retrospectively analyzed the incidence of provoked spasm, complications during testing and the cardiac events after these tests. From January 1991 and October 2018, we performed pharmacological spasm provocation tests in 2500 patients: 1810 ACh tests, 1232 ER tests, 542 both tests, and 310 ACh added after ER tests. ACh was injected in incremental doses of 20/50/100/200 µg into the LCA and 20/50/80 µg into the RCA. ER was administered as a total dose of 64 µg into the LCA and 40 µg into the RCA. When adding ACh after ER, the total dose was 50/80 µg into the RCA and 100/200 µg into the LCA. Positive spasm was defined as ≥ 90% stenosis and usual chest pain or ischemic ECG changes. Mean follow-up duration was 47.5 ± 29.9 months. Overall, provoked positive spasm was found in 1095 patients (43.8%). The incidence of positive provoked spasm during ACh testing was significantly higher than that during other tests (ACh: 48.7% vs. ER: 28.9%, Both: 24%, ACh added after ER: 33.5%, p < 0.001). Multiple spasms were remarkably more frequent during ACh testing compared with the other 3 types of testing (ACh: 28.2% vs. ER: 7.4%, Both: 4.1%, ACh added after ER: 13.2%, p < 0.001). No death or acute myocardial infarction was observed, while major complications during ACh testing were significantly more frequent than during ER testing. Readmission due to recurrent angina pectoris in spasm-positive patients was remarkably more frequent than in spasm-negative patients. The incidence of sudden cardiac death, ventricular fibrillation, and acute coronary syndrome were not different between the spasm-positive and spasm-negative groups during the follow-up periods. We could perform all spasm provocation tests without any irreversible complications. All sequential spasm provocation tests were useful for documenting coronary spasm.

Acetylcholine spasm provocation test by trans-radial artery and brachial vein approach.

BACKGROUND: Temporary pace maker is necessary because of transient block or bradycardia during the intracoronary acetylcholine spasm provocation tests based on the Japanese Circulation Society guidelines. OBJECTIVES: We examined the feasibility and safety of the acetylcholine spasm provocation test via the radial artery and brachial vein approach. METHODS: We tried to perform the acetylcholine spasm provocation tests in 252 patients via the radial artery and brachial vein approach procedures during 5 years. Acetylcholine was injected in incremental doses of 20/50/80 µg into the right coronary artery (RCA) and 20/50/100/200 µg into the left coronary artery (LCA). Back-up pacing rate was set at 40 beats/min. Positive spasm was defined as transient ≥90% luminal narrowing and ischemic electrocardiographic change or usual chest pain. RESULTS: The procedure success of radial artery and brachial vein access was 94.4% (238/252) and 93.3% (235/252), respectively. We performed 221 patients (87.7%) with acetylcholine tests by radial artery and brachial vein approach. We changed to the brachial approach due to the failures of radial artery access in 14 patients. We also changed to the femoral vein in 11 patients and internal jugular vein in two patients. Back-up pace maker rhythm was observed in 92.1% (232/252) of all study patients, while it was significantly higher in the RCA testing than that in the LCA tests (84.9% (191/225) vs. 52.2% (131/251), P < 0.001). No irreversible complication was found. CONCLUSIONS: We recommend the radial artery and brachial vein approach for safety and convenience when performing the acetylcholine spasm provocation tests.

Overview of complications during pharmacological spasm provocation tests.

Pharmacological spasm provocation tests are invasive methods and we always have the potential to encounter complications when performing these tests. In 1980, Buxton et al. reported three deaths when they performed intravenous ergonovine testing. However, we now employ the intracoronary ergonovine test instead of the intravenous injection of ergonovine from a safety procedure point of view. Past serious major complications of intravenous ergonovine tests, intracoronary ergonovine tests, and intracoronary acetylcholine tests were 0.31% (26/8419), 0.51% (11/2173), and 0.95% (148/15,527), respectively. Selective intracoronary testing had the serious major complications in 0.89% of patients including just one death (0.006%) and two acute myocardial infarctions (0.01%). Selective spasm provocation tests had no additional risks compared with performing diagnostic coronary angiography alone. In the Western countries, the pharmacological spasm provocation tests are not familiar in the clinic except for some specialized institutions. We need international clinical studies using the same protocol of spasm provocation tests to compare the frequency, clinical features, and prognosis of acetylcholine- or ergonovine-provoked coronary spasm between Western and Asian countries. And we hope that Western guidelines give spasm provocation testing a class I indication similar to Japanese Circulation Society guidelines because coronary artery spasm may have fewer racial differences and borders.

Serious cardiac complications in coronary spasm provocation tests using acetylcholine or ergonovine: analysis of 21 512 patients from the diagnosis procedure combination database in Japan.

BACKGROUND: Previous studies on complications with coronary spasm provocation tests were based on small sample sizes or were limited to high-volume centers. The risk of provocation tests using acetylcholine (ACH) or ergonovine (ER) remains to be fully examined by a large-scale multicenter study. HYPOTHESIS: ACH provocation tests are associated with a higher rate of serious cardiac complications than ER tests. METHODS: Using the Diagnosis Procedure Combination database in Japan, we identified patients aged ≥20 years who underwent a pharmacological provocation test during coronary angiography. We assessed the composite outcome of cardiac complications requiring urgent procedures (defibrillation, chest compression, intra-aortic balloon pumping, or extracorporeal membrane oxygenation) or death on the day of the provocation test, and compared the outcome between ACH and ER tests. RESULTS: Of 21 512 eligible patients in 602 hospitals, 10 628 (49.4%) underwent an ACH test and 10 884 (50.6%) underwent an ER test. The composite outcome occurred in 141 (0.7%) patients. The ACH group was significantly more likely to have the composite outcome than the ER group (0.9% vs 0.4%, P < 0.001). The propensity-score analyses showed consistent results (propensity score-matched, 0.9% vs 0.4%, P = 0.003; inverse probability-weighted, 0.8% vs 0.4%, P < 0.001). In a multivariable logistic regression analysis, ACH tests were significantly associated with a higher rate of the composite outcome than ER tests (odds ratio: 1.75, 95% confidence interval: 1.13-2.69, P = 0.011). CONCLUSIONS: This retrospective cohort study suggested that ACH tests were associated with a higher rate of cardiac complications than ER tests.

Screening for cardiovascular disease in the young.

America's youth have been screened for cardiovascular disorders for nearly a century. Initial efforts to detect rheumatic heart disease in schoolchildren have gradually shifted to the detection of congenital heart disease in the fetus and newborn, and to the prevention of sudden cardiac death in older children, especially athletes. Proposed screening programs need to consider sensitivity and specificity, cost, resource availability, and the potential for adverse effects of the screening process.

Low-level ionizing radiation from noninvasive cardiac imaging: can we extrapolate estimated risks from epidemiologic data to the clinical setting?

Clinical decision-making regarding the use of low-level ionizing radiation for diagnostic and/or therapeutic purposes in patients with cardiovascular disease must, as in all other clinical scenarios, encompass the broad range of the risk-benefit ratio. Concerns regarding the late carcinogenic effects of exposure to low levels, i.e., <100 mSv, of ionizing radiation stem from extrapolation of exposure-outcome data in survivors of World War II atomic bomb explosions. However, ongoing debate regarding the true incremental risk to subjects exposed to doses currently administered in cardiovascular procedures fails to take into account the uncertainty of the dose-response relationship in this lower range, as well as tissue-specific reparative responses, also manifest at lower levels of exposure. The present discussion draws attention to both of these aspects as they relate to clinical decision-making.

Weighing the risks and benefits of cardiac imaging with ionizing radiation.

The potential risk of fatal malignancy related to cardiac imaging with ionizing radiation is frequently discussed in the medical literature and in the lay press. Clinicians must weigh this risk against the potential benefits of cardiac imaging, which are typically not considered in these reports about radiation risk. This review summarizes the evidence regarding both the radiation risks and clinical benefits of cardiac imaging to provide guidance to the clinician in specific clinical scenarios. Choosing the right test for the right patient, and performing it with the lowest possible radiation dose, remains a challenge.

Epinephrine-induced QT interval prolongation: a gene-specific paradoxical response in congenital long QT syndrome.

OBJECTIVE: To determine the effect of epinephrine on the QT interval in patients with genotyped long QT syndrome (LQTS). PATIENTS AND METHODS: Between May 1999 and April 2001, 37 patients (24 females) with genotyped LQTS (19 LQT1, 15 LQT2, 3 LQT3, mean age, 27 years; range, 10-53 years) from 21 different kindreds and 27 (16 females) controls (mean age, 31 years; range, 13-45 years) were studied at baseline and during gradually increasing doses of intravenous epinephrine infusion (0.05, 0.1, 0.2, and 0.3 microg x k(-1) x min(-1)). The 12-lead electrocardiogram was monitored continuously, and heart rate, QT, and corrected QT interval (QTc) were measured during each study stage. RESULTS: There was no significant difference in resting heart rate or chronotropic response to epinephrine between LQTS patients and controls. The mean +/- SD baseline QTc was greater in LQTS patients (500+/-68 ms) than in controls (436+/-19 ms, P<.001). However, 9 (47%) of 19 KVLQT1-genotyped LQT1 patients had a nondiagnostic resting QTc (<460 milliseconds), whereas 11 (41%) of 27 controls had a resting QTc higher than 440 milliseconds. During epinephrine infusion, every LQT1 patient manifested prolongation of the QT interval (paradoxical response), whereas healthy controls and patients with either LQT2 or LQT3 tended to have shortened QT intervals (P<.001). The maximum mean +/- SD change in QT (AQT [epinephrine QT minus baseline QT]) was -5+/-47 ms (controls), +94+/-31 ms (LQT1), and -87+/-67 ms (LQT2 and LQT3 patients). Of 27 controls, 6 had lengthening of their QT intervals (AQT >30 milliseconds) during high-dose epinephrine. Low-dose epinephrine (0.05 microg x kg(-1) x min(-1)) completely discriminated LQT1 patients (AQT, +82+/-34 ms) from controls (AQT, -7+/-13 ms; P<.001). Epinephrine-triggered nonsustained ventricular tachycardia occurred in 2 patients with LQTS and in 1 control. CONCLUSIONS: Epinephrine-induced prolongation of the QT interval appears pathognomonic for LQT1. Low-dose epinephrine infusion distinguishes controls from patients with concealed LQT1 manifesting an equivocal QTc at rest. Thus, epinephrine provocation may help unmask some patients with concealed LQTS and strategically direct molecular genetic testing.

Negative impact of cardiac evaluation before vascular surgery.

The optimal preoperative evaluation of cardiac risk in patients with peripheral vascular disease is controversial. In developing a paradigm for preoperative cardiac workup, potential adverse effects of evaluation and cardiac intervention must be considered. This study analyzed the deleterious outcomes of extensive, comprehensive cardiac evaluation and intervention before planned vascular surgery in patients treated at the Denver Department of Veterans Affairs Medical Center. Over a 12-month period between 1994 and 1995, 161 patients were scheduled to undergo major vascular operations; 153 patients came to operation. The decision to pursue a cardiac evaluation was variously made by a combination of surgeons, cardiologists, and anesthesiologists. No defined protocol was followed. Cardiac history, chest X-rays and ECGs were obtained for all patients. Extended cardiac evaluation included these studies plus special tests, including echocardiography (echo), radionuclide ventriculography (RNVG), dipyridamole thallium scintigraphy (DTS), and cardiac catheterization (CC). Extended cardiac evaluations were undertaken in 42 patients. Complications related to percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass grafting (CABG) were also recorded. Cardiac mortality and morbidity after vascular interventions were itemized in all 153 patients. Forty-two male patients, aged 68 +/- 9 years, underwent extended cardiac evaluations before planned vascular operations. The median elapsed time for cardiac workup was 14 days (mean 30 +/- 59 days). The median and mean times from cardiac workup to vascular surgery were 25 days and 76 +/- 142 days, respectively. Eighteen (43%) patients had echo or RNVG; 22 (52%) patients had DTS; 27 (64%) had CC; 9 (21%) had PTCA; 7 (17%) had CABG. Sixteen (38%) patients had untoward events related to cardiac evaluation. Eight patients (19%: one with cerebrovascular disease, and seven with aortic aneurysms) refused vascular surgery after extended cardiac workup. Complications attributable to CC, PTCA, and CABG included prosthetic graft infection, pseudoaneurysms (two), sternal wound infections (two), renal failure and brain anoxia. Two patients with severe limb ischemia who were candidates for revascularization ultimately required amputations because of delay due to cardiac evaluations. Extensive cardiac evaluation prior to vascular operations can result in morbidity, delays, and refusal to undergo vascular surgery. The underlying indication for vascular operations and the local iatrogenic cardiac complication rates must be considered before ordering special studies.

[Malignant vasovagal syncope: a case of prolonged asystole induced by the "tilt" test and aggravated by therapy with a beta blocker (a clinical case and diagnostic, physiopathologic and therapeutic review)]. / Síncope vasovagal maligna: um caso de assistolia prolongada induzida pelo teste de "tilt" e agravada pela terapêutica com bloqueador beta (caso clínico e revisão diagnóstica, fisiopatológica e terapêutica).

The authors describe a case of a middle-age male with recurrent syncope, in whom the tilt test was useful in the diagnosis and therapeutic evaluation. Malignant criteria of vasovagal syncope were established and the beta blocking worsening effect was documented, in spite of the general agreement of the first choice drug.

[Risk of cardiological interventions]. / Risiko kardiologischer Eingriffe.

The risk of cardiac interventions has to be assessed in relation to the possible benefit and in comparison to the natural history and to alternative interventions. The relationship between complications (mortality, morbidity) and age, severity of the disease, gender and technique on one hand, and between risk of the intervention versus risk of uninfluenced natural history on the other, are discussed. Diagnostic, therapeutic and prophylactic interventions are presented separately; the benefit needs to be defined differently for each: diagnostic accuracy or symptom relief, improved quality of life and survival, and prolonged life respectively. Finally, it is stressed that the choice of an intervention is not only dependent on the determinants of risk, but also on the availability of a certain method, operator experience, cost and, last but not least, patient preference.

Non Q-wave myocardial infarction following hyperventilation test.

We report a case of acute myocardial infarction following a hyperventilation test performed at coronary angiography. The potential pathophysiological mechanisms and clinical implications are discussed.