Nonischemic chest pain induced by coronary interventions: a prospective study comparing coronary angioplasty and stent implantation

Incidence and Factors Associated With Post-Sternotomy Pain Syndrome in the National Heart Institute, Malaysia

OBJECTIVE

To determine the incidence of poststernotomy pain syndrome (PSPS) after open cardiac surgery in 2021. To determine characteristics and assess the severity of symptoms in patients diagnosed with PSPS. To identify factors that can be associated with patients who were positive for PSPS.

DESIGN AND METHODOLOGY

This study used a retrospective observational approach. Logistic regression analysis was employed to identify factors associated with the positive group.

SETTING

This study included all adult patients who underwent open cardiac surgery at the National Heart Institute, Malaysia, in 2021.

PARTICIPANTS

A total of 1,395 patients were enrolled.

INTERVENTIONS

The study involved conducting phone interviews to assess the presence of PSPS, followed by administering the Brief Pain Inventory questionnaire in the positive group to identify characteristics and severity of chronic pain.

MEASUREMENTS AND MAIN RESULTS

The incidence of PSPS after open cardiac surgery in 2021 was 20.35%. A total of 17.7% of patients reported that pain affected their daily activities, sleep, or emotions. Univariate analysis identified factors associated with PSPS, including age <60 years old, body mass index >30 kg/m2, history of previous percutaneous coronary intervention, ejection fraction <50%, the absence of chronic kidney disease (CKD), and internal mammary artery harvesting (p < 0.05). Multivariate analysis revealed that 4 independent factors were associated with PSPS: age <60 years old, history of previous percutaneous coronary intervention, ejection fraction <50%, and the absence of CKD (as compared with CKD) (p < 0.05).

CONCLUSIONS

Poststernotomy pain syndrome is a complex issue affected by various factors. Although the pain score may not be as severe as previously believed, it remains crucial to recognize PSPS because a significant proportion of patients are affected.

Impact of residual angina on long-term clinical outcomes after percutaneous coronary intervention or coronary artery bypass graft for complex coronary artery disease

AIMS

The aim of this study was to investigate the impact on 10-year survival of patient-reported anginal status at 1 year following percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG) in patients with left main coronary artery disease (LMCAD) and/or three-vessel CAD (3VD).

METHODS AND RESULTS

In this post hoc analysis of the randomized SYNTAX Extended Survival study, patients were classified as having residual angina (RA) if their self-reported Seattle Angina Questionnaire angina frequency (SAQ-AF) scale was ≤90 at the 1-year follow-up post-revascularization with PCI or CABG. The primary endpoint of all-cause death at 10 years was compared between the RA and no-RA groups. A sensitivity analysis was performed using a 6-month SAQ-AF.At 1 year, 373 (26.1%) out of 1428 patients reported RA. Whilst RA at 1 year was an independent correlate of repeat revascularization at 5 years [18.3 vs. 11.5%; adjusted hazard ratio (HR): 1.54; 95% confidence interval (CI): 1.10-2.15], it was not associated with all-cause death at 10 years (22.1 vs. 21.6%; adjusted HR: 1.11; 95% CI: 0.83-1.47). These results were consistent when stratified by the modality of revascularization (PCI or CABG) or by anginal frequency. The sensitivity analysis replicating the analyses based on 6-month angina status resulted in similar findings.

CONCLUSION

Among patients with LMCAD and/or 3VD, patient-reported RA at 1 year post-revascularization was independently associated with repeat revascularization at 5 years; however, it did not significantly increase 10-year mortality, irrespective of the primary modality of revascularization or severity of RA.

Early Post-Percutaneous Coronary Intervention Chest Pain: A Nationwide Survey on Interventional Cardiologists' Perspective

BACKGROUND

Early post-percutaneous coronary intervention chest pain (EPPCP) appears to be a common clinical phenomenon. EPPCP has not been fully explained or studied in the literature despite the abundance of clinical trials on percutaneous coronary intervention (PCI). The objective of this questionnaire-based survey is to assess the current perception of EPPCP among practicing interventional cardiologists nationwide.

METHODS

A survey questionnaire was designed utilizing the Survey Monkey tool to address the perceptions and current practices regarding key aspects of EPPCP among interventional cardiologists. The survey was sent to the interventional cardiologists via email.

RESULTS

The survey questionnaire regarding EPPCP was provided to 2615 practicing interventional cardiologists and resulted in 623 total survey responses, with 503 of those respondents completing all eight survey questions. A total of 50.2% of the interventional cardiologists perceive that the incidence of EPPCP is 5-10%, and 57.5% consider that repeat angiography or PCI is rarely needed (1 in 1000 cases). A total of 47.1% of the participants think that EPPCP is due to transient microvascular dysfunction, while 39% perceive it as a different entity requiring a different approach. When asked about developing a standardized labeling for the phenomenon of EPPCP, 34.8% of responders indicated that they believe EPPCP should be labeled as a benign form of chest pain/angina, and 28% preferred to describe EPPCP in non-standardized terms. Among interventional cardiologists, 80% thought that the treatment of this entity is a combination of reassurance and vasodilators and, without ischemic ECG changes, medical management is appropriate.

CONCLUSION

A total of 72% of interventional cardiologists in our survey preferred to label EPPCP as standard nomenclature to facilitate communication between healthcare providers, patients and families in a consistent way. There is a diversity of opinion regarding EPPCP, no standard nomenclature, and no guideline to standardize practice. Further large-scale prospective studies are needed to better understand the pathophysiological mechanisms, optimal management strategies, prognostic implications, and clinical reporting of EPPCP.

Advances in Cardiac Biomarkers of Acute Coronary Syndrome

Acute coronary syndrome (ACS) encompasses a pathophysiological spectrum of cardiovascular diseases, all of which have significant morbidity and mortality. ACS was once considered an acute condition; however, new treatment strategies and improvements in biomarker assays have led to ACS being an acute and chronic disease. Cardiac troponin is the preferred biomarker for the diagnosis of myocardial infarction, and there is considerable interest and efforts toward development and implementation of high-sensitivity cardiac troponin (hs-cTn) assays worldwide. Analytical and clinical performance characteristics of hs-cTn assays as well as testing limitations are important for laboratorians and clinicians to understand in order to utilize testing appropriately. Furthermore, expanding the clinical utility of hs-cTn into other cohorts such as asymptomatic community dwelling populations, heart failure, and chronic kidney disease populations supports novel opportunities for improved short- and long-term prognosis.

Chest pain after percutaneous coronary intervention in patients with stable angina

BACKGROUND

Percutaneous coronary intervention (PCI) has been widely used to treat acute coronary syndrome but is only recommended as an additional treatment to medical therapy and risk modification in patients with refractory or progressing angina. The number of PCI in this patient population is still increasing. Post-PCI chest pain (PPCP) is one of the common problems of PCI. Its presentation and causes in patients with stable angina are poorly understood.

PATIENTS AND METHODS

This study retrospectively collected clinical information of 167 patients who had stable angina and underwent elective PCI, including 70 patients with PPCP 24 hours after procedure and 97 patients without PPCP. The incidence and predictors of PPCP were analyzed.

RESULTS

The incidence of PPCP was 41.9% (70/167). Compared with non-PPCP patients, PPCP patients had more abnormal post-PCI electrocardiogram (ECG) changes (new Q-waves, ST-segment shifts, or T-waves inversion) and serum cardiac troponin I (cTnI) elevation, more PCI vessels, and stent placement (all P<0.05). More PPCP patients required repeat revascularization than non-PPCP patients after PCI (P=0.043). PPCP was correlated with abnormal post-PCI ECG changes (P<0.0001), cTnI elevation (P<0.0001), post-PCI serum level of cTnI (P<0.0001), number of stents placed (P=0.009), and pre-PCI cTnI level (P=0.049). The strongest predictors of PPCP were abnormal post-PCI ECG changes (P<0.0001), post-PCI cTnI level (P<0.0001), and cTnI elevation (P<0.0001), followed by the number of stents placed (P=0.048).

CONCLUSION

PPCP is common in patients with stable angina in our cohort. It is associated with abnormal ECG changes, cTnI elevation, and number of stents placed.

Aspiration Thrombectomy and Drug-Eluting Stent Implantation Decrease the Occurrence of Angina Pectoris One Year After Acute Myocardial Infarction

Angina pectoris is a treatable symptom that is associated with mortality and decreased quality of life. Angina eradication is a primary care goal of care after an acute myocardial infarction (AMI). Our aim was to evaluate factors influencing angina pectoris 1 year after an AMI.From January 2005 to December 2013, 1547 patient received primary percutaneous intervention in our hospital for an acute ST-segment elevation myocardial infarction (MI). Of these patients, 1336 patients did not experience post-MI angina during a 1-year follow-up, and 211 patients did. Univariate and multivariate logistic regression analyses were performed to identify the factors influencing angina pectoris 1 year after an AMI. Propensity score matched analyses were performed for subgroups analyses.The average age of the patients was 61.08 ± 12.77 years, with a range of 25 to 97 years, and 82.9% of the patients were male. During 1-year follow-up, 13.6% of the patients experienced post-MI angina. There was a longer chest pain-to-reperfusion time in the post-MI angina group (P = 0.01), as well as a higher fasting sugar level, glycohemoglobin (HbA1C), serum creatinine, troponin-I and creatine kinase MB (CK-MB). The post-MI angina group also had a higher prevalence of multiple-vessel disease. Manual thrombectomy, and distal protective device and intracoronary glycoprotein IIb/IIIa inhibitor injection were used frequently in the no post-MI angina group. Antiplatelet agents and post-MI medication usage were similar between the 2 groups. Multivariate logistic regression analyses demonstrated that prior MI was a positive independent predictor of occurrence of post-MI angina. Manual thrombectomy use and drug-eluting stent implantation were negative independent predictors of post-MI angina. Higher troponin-I and longer chest pain-to-reperfusion time exhibited a trend toward predicting post-MI angina.Prior MIs were strong, independent predictors of post-MI angina. Manual thrombectomy and drug-eluting stent implantation could decrease the occurrence of angina pectoris 1 year after an AMI, decrease long-term healthy costs, and increase post-MI quality of life.

Frequency of Angina Pectoris After Percutaneous Coronary Intervention and the Effect of Metallic Stent Type

Although metallic coronary stents significantly reduce angina pectoris compared with optimal medical therapy, angina after percutaneous coronary intervention (PCI) remains frequent. We, therefore, sought to compare the incidence of any angina during the 1 year after PCI among the spectrum of commercially available metallic stents. Metallic stent type was classified as bare metal stent, Cypher, Taxus Express, Xience V, Promus Element, and Resolute. The primary end point was patient-reported angina within 1 year of PCI. Multivariable logistic regression was performed to assess the independent association of stent type with any angina at 1 year. Overall, 8,804 patients were queried in regard to angina symptoms; 32.3% experienced angina at some point in the first year after PCI. Major adverse cardiovascular events, a composite of all-cause mortality, target vessel revascularization, and Q-wave myocardial infarction, increased with angina severity: 6.8% for patients without angina, 10.0% for patients with class 1 or 2 angina, and 19.7% for patients with class 3 or 4 angina (p <0.001 for trend). After multivariable adjustment, there was no significant association between stent type and angina at 1 year after PCI. Baseline Canadian Cardiovascular Society class 3 or 4 angina, history of coronary artery bypass grafting, and history of PCI were associated with a higher likelihood of angina at 1 year; increasing age, male gender, presentation with acute coronary syndrome, and higher stented length were associated with less angina. In conclusion, metallic stent type is not associated with the occurrence of angina at up to 1 year after PCI.

Comparison of acute gain and late lumen loss after PCI with bioresorbable vascular scaffolds versus everolimus-eluting stents: an exploratory observational study prior to a randomised trial

AIMS

The study sought to compare the acute gain and two-year follow-up late lumen loss (LLL) between the Absorb bioresorbable vascular scaffold (BVS) and the analogous everolimus-eluting metallic stent (EES). The current analysis included all the patients recruited in the ABSORB Cohort B and SPIRIT II trials implanted with a single 3.0×18 mm device (Absorb BVS or EES) who underwent serial angiographic examinations at baseline and at two-year follow-up. The acute gain was defined as the difference between post- and preprocedural minimal lumen diameter (MLD). The in-stent/scaffold LLL was calculated as the difference in stent/scaffold segment between the post-procedural MLD and follow-up MLD. Thirty-three patients (33 lesions) implanted with the Absorb BVS, and 26 patients (28 lesions) implanted with the EES were studied. The acute gain was similar in the Absorb BVS group (1.23±0.38 mm) compared to the EES group (1.32±0.26 mm, p=0.29). The in-stent/scaffold LLL at two-year follow-up in the Absorb BVS group (0.26±0.19 mm) was also similar compared to the EES group (0.22±0.22 mm, p=0.29). Although the two groups had similar two-year clinical outcomes (major adverse cardiac events: Absorb BVS: 6.1% vs. EES: 0.0%), patients treated with the Absorb BVS exhibited a significantly lower two-year in-stent/scaffold MLD compared to the EES (2.02±0.26 mm vs. 2.22±0.34 mm, p=0.01). Although BVS and EES demonstrated similar two-year clinical outcomes, patients treated with the Absorb BVS exhibited a significantly lower two-year in-stent/scaffold MLD compared to patients treated with the EES. Appropriately powered randomised trials are necessary to confirm these exploratory results and evaluate their prognostic and clinical significance.

Varying definitions for periprocedural myocardial infarction alter event rates and prognostic implications

BACKGROUND

Periprocedural myocardial infarction (PMI) has had several definitions in the last decade, including the Society for Cardiovascular Angiography and Interventions (SCAI) definition, that requires marked biomarker elevations congruent with surgical PMI criteria.

METHODS AND RESULTS

The aim of this study was to examine the definition-based frequencies of PMI and whether they influenced the reported association between PMI and increased rates of late death/ myocardial infarction (MI). We studied 742 patients; 492 (66%) had normal troponin T (TnT) levels and 250 (34%) had elevated, but stable or falling, TnT levels. PMI, using the 2007 and the 2012 universal definition, occurred in 172 (23.2%) and in 99 (13.3%) patients, respectively, whereas 19 (2.6%) met the SCAI PMI definition (P<0.0001). Among patients with PMI using the 2012 definition, occlusion of a side branch ≤1 mm occurred in 48 patients (48.5%) and was the most common angiographic finding for PMI. The rates of death/MI at 2 years in patients with, compared to those without, PMI was 14.7% versus 10.1% (P=0.087) based on the 2007 definition, 16.9% versus 10.3% (P=0.059) based on the 2012 definition, and 29.4% versus 10.7% (P=0.015) based on the SCAI definition.

CONCLUSION

In this study, PMI, according to the SCAI definition, was associated with more-frequent late death/MI, with ≈20% of all patients, who had PMI using the 2007 universal MI definition, not having SCAI-defined PMI. Categorizing these latter patients as SCAI-defined no PMI did not alter the rate of death/MI among no-PMI patients.

Recurrent angina after coronary angioplasty: mechanisms, diagnostic and therapeutic options

Recurrent angina in patients who underwent percutaneous coronary intervention is defined as recurrence of chest pain or chest discomfort. Careful assessment is recommended to differentiate between non-cardiac and cardiac causes. In the case of the latter, recurrent angina occurrence can be related to structural ('stretch pain', in-stent restenosis, in-stent thrombosis, incomplete revascularization, progression of coronary atherosclerosis) or functional (coronary micro-vascular dysfunction, epicardial coronary spasm) causes. Even though a complete diagnostic algorithm has not been validated, ECG exercise testing, stress imaging and invasive assessment of coronary blood flow and coronary vaso-motion (i.e. coronary flow reserve, provocation testing for coronary spasm) may be required. When repeated coronary revascularization is not indicated, therapeutic approaches should aim at targeting the underlying mechanism for the patient's symptoms using a variety of drugs currently available such as beta-blockers, calcium-channel blockers, ivabradine or ranolazine.

Periprocedural myocardial infarction: review and classification

Technical and pharmacologic advances have reduced the occurrence of large periprocedural myocardial infarction (PMI) after percutaneous coronary interventions (PCI), but PMI still occurs in 6% to 18% of the cases and is associated with impaired short- and long-term survival. PMI might be due to side branch closure or flow-limiting dissection, but is most often diagnosed after apparently uncomplicated PCI and is due to atheroembolization into the microcirculation. Various definitions of PMI are used in clinical trials, but a rise in creatine kinase-MB greater than 3 to 8 times the upper limit of normal is consistently associated with worse prognosis, particularly as it reflects a more extensive and unstable atherosclerotic burden. On the other hand, data regarding the independent prognostic value of periprocedural troponin increase are conflicting. Some data suggest that PMI has a better prognosis than a spontaneously occurring myocardial infarction, and that its incidence is reduced with aggressive antiplatelet and statin therapy.

Chest pain of cardiac and noncardiac origin

Chest pain is one of the most common symptoms driving patients to a physician's office or the hospital's emergency department. In approximately half of the cases, chest pain is of cardiac origin, either ischemic cardiac or nonischemic cardiac disease. The other half is due to noncardiac causes, primarily esophageal disorder. Pain from either origin may occur in the same patient. In addition, psychological and psychiatric factors play a significant role in the perception and severity of the chest pain, irrespective of its cause. Chest pain of ischemic cardiac disease is called angina pectoris. Stable angina may be the prelude of ischemic cardiac disease; and for this reason, it is essential to ensure a correct diagnosis. In most cases, further testing, such as exercise testing and angiography, should be considered. The more severe form of chest pain, unstable angina, also requires a firm diagnosis because it indicates severe coronary disease and is the earliest manifestation of acute myocardial infarction. Once a diagnosis of stable or unstable angina is established, and if a decision is made not to use invasive therapy, such as coronary bypass, percutaneous transluminal coronary angioplasty, or stent insertion, effective medical treatment of associated cardiac risk factors is a must. Acute myocardial infarction occurring after a diagnosis of angina greatly increases the risk of subsequent death. Chest pain in women warrants added attention because women underestimate their likelihood to have coronary heart disease. A factor that complicates the clinical assessment of patients with chest pain (both cardiac and noncardiac in origin) is the relatively common presence of psychological and psychiatric conditions such as depression or panic disorder. These factors have been found to cause or worsen chest pain; but unfortunately, they may not be easily detected. Noncardiac chest pain represents the remaining half of all cases of chest pain. Although there are a number of causes, gastroesophageal disorders are by far the most prevalent, especially gastroesophageal reflux disease. Fortunately, this disease can be diagnosed and treated effectively by proton-pump inhibitors. The other types of non-gastroesophageal reflux disease-related noncardiac chest pain are more difficult to diagnose and treat. In conclusion, the cause of chest pain must be accurately diagnosed; and treatment must be pursued according to the cause, especially if the cause is of cardiac origin.

Chest Symptoms Following Coronary Stenting in the First 10 Weeks of Recovery

Background: Most patients experience the benefits of PTCA and stent quickly, with reduction in symptoms and improvement in functional status, however many patients experience chest symptoms post-procedure.

Objective: To describe the pattern and characteristics of post-stent chest symptoms in cardiac rehabilitation participants.

Methods: A prospective descriptive study assessing the pattern and presence of chest symptoms in coronary artery stent recipients ( N = 129) four and ten weeks post-procedure. Patients were interviewed at cardiac rehabilitation or by the phone using a specifically developed questionnaire which incorporated the McGill Pain Questionnaire.

Results: Most participants were male, aged on average 60.5 years and received two stents, most often drug eluting. Post-stent chest symptoms were common, experienced by two thirds of patients (68%) at some time during the 10 weeks post-discharge. Chest symptoms were recurrent, with 33% having symptoms on both occasions and occurred more often in younger patients ( p < .00). Patients described their symptoms as discomforting and used the descriptors dull, tight, sharp, pressing and flickering. Chest symptoms tended to be brief and/or intermittent (65%) lasting from a few seconds to a few minutes (63%). Most patients felt their symptoms were related to their stent (75%) and were unsure what to do. A small number (5%) interpreted their symptoms as ischaemic and presented to the hospital (4%).

Conclusions: Post-stent chest symptoms are frequent and recurrent out to 10 weeks post-discharge. Although symptoms tended to be brief and intermittent, the location and quality of these symptoms may overlap with existing chest pain guidelines, making it difficult for patients to interpret. Cardiac rehabilitation staff are in an ideal position to support and inform stent recipients about appropriate responses to these symptoms.

Multidetector CT for visualization of coronary stents

Whereas the clinical diagnosis of in-stent thrombosis is straightforward, that of in-stent restenosis remains a problem, because although many patients experience chest pain after coronary stent placement, that symptom is secondary to ischemia in only a few. The use of a noninvasive technique to identify such patients for early invasive intervention versus more conservative management is thus highly desirable. Multidetector computed tomography (CT) performed with 16-section scanners recently emerged as such a technique and has overtaken modalities such as electron-beam CT and magnetic resonance imaging as an alternative to conventional angiography for the assessment of in-stent restenosis. The improved hardware design of the current 64-section CT scanners allows even better delineation of stent struts and lumen. The more reliable criterion of direct lumen visualization thus may be substituted for the presence of distal runoff, which lacks specificity for a determination of in-stent patency because of the possibility of collateral pathways. However, the capability to accurately visualize the in-stent lumen depends partly on knowledge of the causes of artifacts and how they can be compensated for with postprocessing and proper image display settings. In addition, an understanding of the major stent placement techniques used in the treatment of lesions at arterial bifurcations is helpful.

Angiographic adverse events during percutaneous coronary intervention fail to predict creatine kinase-MB elevation

We attempted to determine if aggressive detection of angiographic adverse events during coronary intervention could predict subsequent creatine kinase (CK)-MB elevations. During coronary intervention, both fluoroscopy and cine angiography were used to detect angiographic adverse events. At least one angiographic adverse event occurred in 133/251 (53%) of procedures. CK-MB elevation occurred in 24% of procedures. Slow flow during the procedure (P=0.002) and chest discomfort at the end of the procedure (P=0.007) were the strongest predictors of CK-MB elevation. Among procedures with no angiographic adverse events, CK-MB elevation occurred in 15/121 (12%), accounting for 25% of CK-MB elevations. We conclude that CK-MB elevation occurs after angiographically uncomplicated coronary interventions even when angiographic adverse events are aggressively detected. Routine monitoring of cardiac enzymes is necessary to detect all patients who will experience myocardial injury after coronary intervention.

Remifentanilversus propofol for radio frequency treatment of atrial flutter

PURPOSE

Radio frequency treatment in cardiology generates short acute pain during the heating process. The present study evaluates two techniques used for sedation/analgesia for this procedure.

METHODS

Two groups of 20 patients each were studied prospectively. Patients were randomized to receive sedation for the procedure using either a patient-controlled analgesia device with remifentanil (Group R), or a target controlled infusion of propofol (Group P). Patients in Group R had a basal infusion of remifentanil 0.02-0.04 microg x kg(-1) x min(-1) with self administered bolus doses of 0.3 microg x kg(-1) i.v. every minute as required, with a delivery time greater than 30 sec. Patients in Group P had an initial plasma target concentration set at 3-4 microg x mL(-1).

RESULTS

Sedation scores were significantly higher in Group P, and two patients required supplementation with remifentanil and insertion of an laryngeal mask airway. Pain scores were higher in Group R, and two patients experienced muscular rigidity, one with transient apnea. Systolic blood pressure decreased significantly in Group P, and at the end of the procedure, PaCO(2) values were higher in that group (P < 0.01). Recovery time was significantly longer in Group P. Patient and physician satisfaction scores were similar in the two groups.

CONCLUSIONS

A basal infusion of remifentanil plus remifentanil patient controlled analgesia and target controlled infusion of propofol were adequate but not optimal techniques for sedation/analgesia for radio frequency treatment of atrial flutter.

Coronary artery stent thrombosis associated with exercise testing

Chest pain following coronary artery stenting is common, yet finding the cause can be difficult. Exercise testing has long been used in the assessment of chest pain, but its usefulness in patients who have recently undergone coronary artery stenting is in doubt. A case of exercise testing appearing to precipitate acute stent thrombosis in a patient several weeks post-coronary artery stenting is reported and compared to a similar case in the literature. The role of exercise testing in the assessment of chest pain early after coronary artery stenting is then reviewed.

Peri-procedural myocardial injury: 2005 update

During the past three decades, percutaneous coronary intervention has become one of the cardinal treatment strategies for stenotic coronary artery disease. Technical advances, including the introduction of new devices such as stents, have expanded the interventional capabilities of balloon angioplasty. At the same time, there has been a decline in the rate of major adverse cardiac events, including Q-wave acute myocardial infarction, emergency coronary artery bypass grafting, and cardiac death. Despite these advances, the incidence of post-procedural cardiac marker elevation has not substantially decreased since the first serial assessment 20 years ago. As of now, these post-procedural cardiac marker elevations are considered to represent peri-procedural myocardial injury (PMI) with worse long-term outcome potential. Recent progress has been made for the identification of two main PMI patterns, one near the intervention site (proximal type, PMI type I) and one in the distal perfusion territory of the treated coronary artery (distal type, PMI type II) as well as for preventive strategies. Integrating these new developments into the wealth of clinical information on this topic, this review aims at giving a current perspective on the entity of PMI.

AHA scientific statement: practice standards for electrocardiographic monitoring in hospital settings: an American Heart Association Scientific Statement from the Councils on Cardiovascular Nursing, Clinical Cardiology, and Cardiovascular Disease in the Young: endorsed by the International Society of Computerized electrocardiology and the American Association of Critical-Care Nurses

The goals of electrocardiographic (ECG) monitoring in hospital settings have expanded from simple heart rate and basic rhythm determination to the diagnosis of complex arrhythmias, myocardial ischemia, and prolonged QT interval. Whereas Computerized arrhythmia analysis is automatic in cardiac monitoring systems, computerized ST-segment ischemia analysis is available only in newer-generation monitors, and computerized QT-interval monitoring is currently unavailable. Even in hospitals with ST-monitoring capability, ischemia monitoring is vastly underutilized by healthcare professionals. Moreover, because no computerized analysis is available for QT monitoring, healthcare professionals must determine when it is appropriate to manually measure QT intervals (eg, when a patient is started on a potentially proarrhythmic drug). The purpose of the present review is to provide "best practices" for hospital ECG monitoring. Randomized clinical trials in this area are almost nonexistent; therefore, expert opinions are based upon clinical experience and related research in the field of electrocardiography. This consensus document encompasses all areas of hospital cardiac monitoring in both children and adults. The emphasis is on information clinicians need to know to monitor patients safely and effectively. Recommendations are made with regard to indications, time frames, and strategies to improve the diagnostic accuracy of cardiac arrhythmia, ischemia, and QT-interval monitoring. Currently available ECG lead systems are described, and recommendations related to staffing, training, and methods to improve quality are provided.

Clinical parameters and functional tests are not predictive for in-stent restenosis

OBJECTIVE

To study the correlation between clinical parameters and the occurrence of in-stent restenosis in a cohort of patients from the Tel Aviv Medical Center who underwent repeat angiograms for clinical indications following stenting.

BACKGROUND

After stenting, recurrences of symptoms or ischemia on functional tests are considered to be clinical signs of restenosis.

METHODS

The authors' study group consisted of 149 out of 1469 patients (10%) who underwent stent implantation between 1996 and 1998 and were under clinical follow-up. This group had a repeat angiogram for clinical indications: chest pain or a positive functional test (thallium study or ergometry).

RESULTS

Sixty-eight patients (45%) had in-stent restenosis (ISR), 32 (21%) had a patent stent site with a significant coronary atherosclerosis elsewhere requiring revascularization (NTLR), and 51 (34%) had a patent stent site and did not require additional revascularization (PS). Baseline characteristics were similar in all the groups. There was a 63% rate of objective evidence of ischemia in the PS group, similar to the ISR (63%) and NTLR (74%) groups. In the ISR versus the NTLR and PS groups the stents were longer (22 +/- 10 versus 17 +/- 7 and 16 +/- 6 mm, p < 0.001) with a smaller diameter (3 +/- 0.4 versus 3.3 +/- 0.5 and 3.2 +/- 0.4 mm, p < 0.05) and a higher rate of multiple stents in the target lesion (34% versus 19% and 14%, p < 0.05)

CONCLUSIONS

In the cohort of patients who underwent angiography following stenting for chest pain or a positive functional test, 55% were found to have a patent stent site. The 5% total in-stent restenosis is significantly lower than the rate in angiography-based reports. On the other hand, the group with a patent stent had a higher than expected rate of objective evidence of ischemia. Therefore clinical parameters and functional tests are not predictive for in-stent restenosis.

Patient care before and after percutaneous coronary artery interventions

Care of the patient before and after percutaneous coronary interventions has changed largely because of the increased use of stents. Important patient management issues include the evaluation of chest pain after the procedure, recognition of acute vessel closure during the periprocedural period, management of the vascular access site, and prevention of contrast-induced renal dysfunction. Risk factor modification and drug therapies are important interventions for the secondary prevention of coronary events. Functional testing has a meaningful role in the evaluation of some patients after coronary intervention. It is important for the specialist in internal medicine to have a firm working knowledge of the various aspects of patient care before and after these procedures because their role in the management of these patients is increasing.

A descriptive study of early nonspecific chest pain after PTCA: important area for the acute health care personnel

BACKGROUND

Many patients report chest pain of varying intensity at various locations during the first hours after percutaneous transluminal coronary angioplasty (PTCA).

OBJECTIVES

The aim of the study was to increase knowledge regarding differentiating between harmless chest pain versus ischemic chest pain, focusing on patients description of their pain.

METHODS

A total of 192 patients after elective PTCA were interviewed twice. In addition patients experiencing chest pain within 6 hours after the procedure completed the McGill Pain Questionnaire (MPQ).

RESULTS

Nonspecific chest pain occurred in 34 patients (18%) and ischemic chest pain in 6 (3%), whereas 152 (79%) did not report early chest pain after PTCA. The nonspecific pain group reported statistically significant less pain intensity (VAS P =.001), used fewer (P =.006) and qualitatively weaker (P =.008) words compared to the ischemic pain group. No predisposing factors that could predict chest pain were identified.

CONCLUSIONS

Discriminators appear to be the pain intensity and the word descriptors. MPQ combined with a VAS could be valuable clinical tools with regard to patients' description of pain.

Postprocedure chest pain after coronary stenting: implications on clinical restenosis

OBJECTIVES

The goal of this study was to analyze the incidence and predictors of postprocedure chest pain (PPCP) after percutaneous coronary intervention (PCI) and its correlation with clinical restenosis.

BACKGROUND

Chest pain after PCI occurs frequently even in the absence of procedural events and is considered to be due to vasospasm or coronary artery stretch. The short- and long-term significance of PPCP after otherwise successful stenting is not clear.

METHODS

We analyzed 1,362 patients undergoing coronary stenting for PPCP, procedural and in-hospital events, 30-day major adverse cardiac events, and target vessel revascularization (TVR) at 6 to 9 months.

RESULTS

There were 488 patients with PPCP and, of these, 312 patients were excluded due to procedural events. The remaining 176 patients with PPCP were compared with 874 patients without PPCP. Creatine kinase-MB isoenzyme elevation occurred in 25.6% of the PPCP group versus 9.6% of the no PPCP group (p < 0.001). Despite similar reference vessel diameter, the PPCP group had larger postprocedure minimum lumen diameter, higher stent-to-vessel ratio, and higher inflation pressure versus the no PPCP group (p < 0.01). At 30 days, the emergency room visits and repeat catheterization (16% vs. 2.7%; p < 0.001) were higher in the PPCP group versus the no PPCP group, but repeat intervention was similar. At 6- to 9-month follow-up, the TVR was significantly higher in the PPCP group compared with the no PPCP group (29.5% vs. 16.6%; p < 0.01).

CONCLUSIONS

Our analysis suggests micromyonecrosis and vessel stretch as causes of PPCP. Postprocedure chest pain is associated with similar short-term outcome as no PPCP, but has higher restenosis, perhaps mediated by deep vessel wall injury. Therefore, PPCP may identify patients at high risk for restenosis.

Chest pain after coronary artery stent implantation

A sizeable proportion of patients who undergo successful coronary artery stent implantation experiences chest pain immediately after the procedure and/or in the following months in the absence of in-stent restenosis. We investigated this phenomenon in 57 consecutive patients with stable angina who underwent successful stent implantation. Chest pain characteristics were assessed before stent implantation and during 6-month follow-up. All patients underwent coronary angiography within 6 months of the procedure 48 hours after exercise thallium-201 perfusion scintigraphy. Patients who did not exhibit in-stent restenosis underwent an ergonovine test at the end of routine coronary angiography. During follow-up, 15 patients complained of chest pain. Six of these patients exhibited scintigraphic evidence of myocardial ischemia and in-stent restenosis at angiography. In the remaining 9 patients, chest pain occurred in the absence of in-stent restenosis at angiography. In 8 of these patients intracoronary ergonovine administration reproduced their habitual pain, whereas it did not cause any pain in the 42 patients who were completely asymptomatic at follow-up and without in-stent restenosis. Ergonovine caused more intense vasoconstriction and nitroglycerin caused more intense vasodilation of the reference coronary diameter in patients with than in patients without ergonovine-induced pain (-17 +/- 3 vs -9 +/- 3%, p <0.001; 9 +/- 6 vs 5 +/- 4%, p <0.02, respectively). In conclusion, chest pain with features similar to habitual angina occurs in the absence of in-stent restenosis in 1/5 of patients after stent implantation and appears to be associated with more intense coronary vasoreactivity.

Coronary arterial stent patency: assessment with electron-beam CT

PURPOSE

To evaluate electron-beam computed tomography (CT) for stent localization and noninvasive assessment of stent patency in patients with coronary arterial stents and coronary bypass stents.

MATERIALS AND METHODS

CT in the single-section volume mode was performed in 202 patients with 321 coronary arterial stents in 221 vessels to localize the stents. Patency was evaluated in the multisection flow mode with an intravenous bolus injection of contrast material. All electron-beam CT images were reviewed by an observer who had no knowledge of the coronary angiographic results. Electron-beam CT findings were then compared with coronary angiographic findings.

RESULTS

The stents could be visualized and related to the coronary arterial segments in 216 of 221 vessels with electron-beam CT. Of the 221 vessels, 207 were correctly evaluated with electron-beam CT. Compared with coronary angiography, electron-beam CT permitted the detection of 18 of 23 high-grade stenoses (sensitivity, 78%) and correctly depicted the absence of high-grade stenoses in 189 of 193 vessels with stents (specificity, 98%). Altogether, 18 stenoses were detected correctly at electron-beam CT; the interpretation was false-positive in four vessels (positive predictive value, 82% [18/22 vessels]) and false-negative in five (negative predictive value, 97% [189/194 vessels]).

CONCLUSION

Electron-beam CT may be helpful in localizing intracoronary stents and assessing stent patency noninvasively to delay the intervals between catheterizations in an increasing number of patients.

Chest pain--a strong predictor of adverse cardiac events following precutaneous intervention (from the Evaluation of Platelet IIb/IIIa Inhibitor for Stenting Trial [EPISENT])]

Postprocedural chest pain remains a common problem, and irrespective of electrocardiographic changes, is associated with a higher incidence of early cardiac events. A return to the catheterization laboratory is unlikely to benefit patients with postprocedural chest pain without electrocardiographic changes with documented irreversible intraprocedural complications, or those with late postprocedural pain.

Coronary microembolization--its role in acute coronary syndromes and interventions

The diagnosis coronary artery disease is classically based on patient's symptoms and morphology, as analyzed by angiography. The importance of risk factors for the development of coronary atherosclerosis and disturbance of coronary vasomotion is clearly established. However, microembolization of the coronary circulation has also to be taken into account. Microembolization may occur as a single or as multiple, repetitive events, and it may induce inflammatory responses. Spontaneous microembolization may occur, when the fibrous cap of an atheroma or fibroatheroma (Stary i.v. and Va) ruptures and the lipid pool with or without additional thrombus formation is washed out of the atheroma into the microcirculation. Such events with progressive thrombus formation are known as cyclic flow variations. Plaque rupture occurs more frequently than previously assumed, i.e. in 9% of patients without known heart disease suffering a traffic accident and in 22% of patients with hypertension and diabetes. Also, in patients dying from sudden death microembolization is frequently found. Patients with stable and unstable angina show not only signs of coronary plaque rupture and thrombus formation, but also microemboli and microinfarcts, the only difference between those with stable and unstable angina being the number of events. Appreciation of microembolization may help to better understand the pathogenesis of ischemic cardiomyopathy, diabetic cardiomyopathy and acute coronary syndromes, in particular in patients with normal coronary angiograms, but plaque rupture detected by intravascular ultrasound. Also, the benefit from glycoprotein IIb/IIIa receptor antagonist is better understood, when not only the prevention of thrombus formation in the epicardial atherosclerotic plaque, but also that of microemboli is taken into account. Microembolization also occurs during PTCA, inducing elevations of troponin T and I and elevations of the ST segment in the EKG. Elevated baseline coronary blood flow velocity, as a potential consequence of reactive hyperemia in myocardium surrounding areas of microembolization, is more frequent in patients with high frequency rotablation than in patients with stenting and in patients with PTCA. The hypothesis of iafrogenic microembolization during coronary interventions is now supported by the use of aspiration and filtration devices, where particles with a size of up to 700 microns have been retrieved. In the experiment, microembolization is characterized by perfusion-contraction mismatch, as the proportionate reduction of flow and function seen with an epicardial stenosis is lost and replaced by contractile dysfunction in the absence of reduced flow. The analysis of the coronary microcirculation, in addition to that of the morphology and function of epicardial coronary arteries, and in particular appreciation of the concept of microembolization will further improve the understanding of the pathophysiology and clinical symptoms of coronary artery disease.

Angiographic findings in patients undergoing catheterization for recurrent symptoms within 30 days of successful coronary intervention

In 108 consecutive patients without abrupt vessel closure referred for repeat coronary angiography within 30 days of successful coronary intervention, 28 (26%) were found with restenosis at the treated site. None of the 27 patients who underwent stenting were found to have early restenosis; balloon angioplasty without stenting was the only independent predictor of early restenosis in patients with recurrent symptoms within 30 days of intervention.

Aortic pain: the renaissance of cardiovascular pain and the detection of aortopathy

Our 19th century predecessors considered the aorta as a source of cardiovascular pain associated with inflammatory aortitis, arterial hypertension, aortic aneurysms, aortic dissection, and aortic valve disease. However, during the 20th century epidemic of coronary artery disease clinicians became concerned with the syndromes associated with myocardial ischemia and infarction, relegating aortic pain syndromes to the role of a differential, "rule out", or diagnosis of exclusion rather than a primary diagnosis. We re-focus attention on a more global approach to cardiovascular pain, approaching thoracic aortic pain syndromes as primary diagnoses, while considering the dynamics and various stages of development of aortic pain syndromes, set within the clinical environment in which these syndromes arise. The central role of aortopathy is our underlying theme since the detection and clinical recognition of aortopathic disorders provide the template for identification of the population at risk for aortic pain syndromes. Clinical history, pedigree development, phenotype recognition, analysis of the elastic properties of the aorta, use of the wide range of sophisticated imaging techniques, and phenotype-genotype correlations provide the bases for the recognition, diagnosis, and management of aortopathy within the clinical setting. A futuristic anticipatory approach towards the diagnosis of aortopathy is outlined with emphasis on earlier recognition and informed clinical management ultimately leading to prevention of the acute and dynamic aortic complications.

Chest pain after coronary interventional procedures. Incidence and pathophysiology

Chest pain following successful percutaneous coronary interventions is a common problem. Although the development of chest pain after coronary interventions may be of benign character, it is disturbing to patients, relatives and hospital staff. Such pain may be indicative of acute coronary artery closure, coronary artery spasm or myocardial infarction, but may also simply reflect local coronary artery trauma. The distinction between these causes of chest pain is crucial in selecting optimal care. Management of these patients may involve repeat coronary angiography and additional intervention. Commonly, repeat coronary angiography following percutaneous transluminal coronary angioplasty (PTCA) in patients with chest pain demonstrates widely patent lesion sites suggesting that the pain was due to coronary artery spasm, coronary arterial wall stretching or was of non-cardiac origin. As reported by the National Heart, Lung and Blood Institute PTCA Registry, 4.6% of patients after angioplasty have coronary occlusions, 4.8% suffer a myocardial infarction, and 4.2% have coronary spasm. The frequency of chest pain after new device coronary interventions (atherectomy and stenting) seems to be even higher. However, only the minority of patients with post-procedural chest pain have indeed an ischemic event. Therefore, the vast majority of patients have recurrent chest pain without any signs of ischemia. There is some evidence that non-ischemic chest pain after coronary interventions is more common after stent implantation as compared to PTCA (41% vs. 12%). This may be due to the continuous stretching of the arterial wall by the stent as the elastic recoil occurring after PTCA is minimized. In conclusion, chest pain after coronary interventional procedures may potentially be hazardous when due to myocardial ischemia. However, especially after coronary stent placement, cardiologists must consider "stretch pain" due to the overdilation and stretching of the artery caused by the stent in the differential diagnosis. Clinically, it is, therefore, important to recognize that in addition to ischemia-related chest pain other types of chest pain do exist with cardiac origin.