Successful percutaneous coronary intervention to the left anterior descending artery in-stent chronic total occlusion via the left internal mammary artery graft: a case report.

BACKGROUND: Percutaneous coronary intervention (PCI) via left internal mammary artery (LIMA) graft is technically challenging, requires special consideration due to association with potential complications and therefore, infrequently performed. Data on in-stent chronic total occlusion (CTO) PCI via the LIMA graft is even rarer. CASE SUMMARY: A 59-year-old male with a background history of coronary artery bypass graft surgery and previous PCI, presented with progressive chest pain on mild exertion, in the setting of a chronic coronary syndrome. Transradial coronary angiography revealed significant native three-vessel disease with CTO of right coronary, left anterior descending (LAD) and left circumflex arteries. Left internal mammary artery-LAD was widely patent. The previous LIMA-LAD stent at the anastomosis had a CTO with severe in-stent restenosis (ISR) at the distal end of the stent in the native LAD. The distal LAD was filled from bridging collaterals. Following discussion at the heart team meeting, he underwent successful complex PCI of LAD CTO via the LIMA graft at the site of ISR of previous LIMA-LAD anastomosis stent, which was finally treated with drug-coated balloon (DCB) angioplasty. DISCUSSION: Recurrent angina post-coronary revascularization can be very challenging to manage by medical therapy alone. Percutaneous intervention of complex coronary lesions in these patients requires experience and skill, especially when approaching lesions using the LIMA as a conduit. The use of DCB for ISR management is a well-known strategy; however, adequate lesion preparation is the key to satisfactory outcome.

Human-Computer Agreement of Electrocardiogram Interpretation for Patients Referred to and Declined for Primary Percutaneous Coronary Intervention: Retrospective Data Analysis Study.

BACKGROUND: When a patient is suspected of having an acute myocardial infarction, they are accepted or declined for primary percutaneous coronary intervention partly based on clinical assessment of their 12-lead electrocardiogram (ECG) and ST-elevation myocardial infarction criteria. OBJECTIVE: We retrospectively determined the agreement rate between human (specialists called activator nurses) and computer interpretations of ECGs of patients who were declined for primary percutaneous coronary intervention. METHODS: Various features of patients who were referred for primary percutaneous coronary intervention were analyzed. Both the human and computer ECG interpretations were simplified to either "suggesting" or "not suggesting" acute myocardial infarction to avoid analysis of complex heterogeneous and synonymous diagnostic terms. Analyses, to measure agreement, and logistic regression, to determine if these ECG interpretations (and other variables such as patient age, chest pain) could predict patient mortality, were carried out. RESULTS: Of a total of 1464 patients referred to and declined for primary percutaneous coronary intervention, 722 (49.3%) computer diagnoses suggested acute myocardial infarction, whereas 634 (43.3%) of the human interpretations suggested acute myocardial infarction (P<.001). The human and computer agreed that there was a possible acute myocardial infarction for 342 out of 1464 (23.3%) patients. However, there was a higher rate of human-computer agreement for patients not having acute myocardial infarctions (450/1464, 30.7%). The overall agreement rate was 54.1% (792/1464). Cohen κ showed poor agreement (κ=0.08, P=.001). Only the age (odds ratio [OR] 1.07, 95% CI 1.05-1.09) and chest pain (OR 0.59, 95% CI 0.39-0.89) independent variables were statistically significant (P=.008) in predicting mortality after 30 days and 1 year. The odds for mortality within 1 year of referral were lower in patients with chest pain compared to those patients without chest pain. A referral being out of hours was a trending variable (OR 1.41, 95% CI 0.95-2.11, P=.09) for predicting the odds of 1-year mortality. CONCLUSIONS: Mortality in patients who were declined for primary percutaneous coronary intervention was higher than the reported mortality for ST-elevation myocardial infarction patients at 1 year. Agreement between computerized and human ECG interpretation is poor, perhaps leading to a high rate of inappropriate referrals. Work is needed to improve computer and human decision making when reading ECGs to ensure that patients are referred to the correct treatment facility for time-critical therapy.

Efficacy of RADPAD® protection drape in reducing radiation exposure to the primary operator during Transcatheter Aortic Valve Implantation (TAVI).

BACKGROUND: The efficacy of RADPAD® (a sterile, lead-free drape) has been demonstrated to reduce the scatter radiation to the primary operator during fluoroscopic procedures. However, the use of the RADPAD® during TAVI procedures has not been studied. Transcatheter aortic valve implantation (TAVI) is now an established treatment for patients with symptomatic severe aortic stenosis who are deemed inoperable or at high risk for conventional surgical aortic valve replacement (AVR). Consequently the radiation exposure to the patient and the interventional team from this procedure has become a matter of interest and importance. Methods to reduce radiation exposure to the interventional team during this procedure should be actively investigated. In this single center prospective study, we determined the radiation dose during this procedure and the efficacy of RADPAD® in reducing the radiation dose to the primary operator. METHODS: Fifty consecutive patients due to undergo elective TAVI procedures were identified. Patients were randomly assigned to undergo the procedure with or without the use of a RADPAD® drape. There were 25 patients in each group and dosimetry was performed at the left eye level of the primary operator. The dosimeter was commenced at the start of the procedure, and the dose was recorded immediately after the end of the procedure. Fluoroscopy times and DAP were also recorded prospectively. RESULTS: Twenty-five patients underwent transfemoral TAVI using a RADPAD® and 25 with no-RADPAD®. The mean primary operator radiation dose was significantly lower in the RADPAD group at 14.8 mSv vs. 24.3 mSv in the no-RADPAD group (P=0.008). There was no significant difference in fluoroscopy times or dose-area products between the two patient groups. The dose to the primary operator relative to fluoroscopy time (RADPAD: slope=0.325; no RADPAD: slope=1.148; analysis of covariance F=7.47, P=0.009) and dose area product (RADPAD: slope=0.0007; no RADPAD: slope=0.002; analysis of covariance F=7.38; P=0.009) was smaller in the RADPAD group compared to no-RADPAD group. CONCLUSIONS: Use of a RADPAD® significantly reduces radiation exposure to the primary operator during TAVI procedures.

Using computerised interactive response technology to assess electrocardiographers and for aggregating diagnoses.

The 12-lead electrocardiogram (ECG) is a crucial diagnostic tool. However, the ideal method to assess competency in ECG interpretation remains unclear. We sought to evaluate whether keypad response technology provides a rapid, interactive way to assess ECG knowledge. 75 participants were enrolled [32 (43%) Primary Care Physicians, 24 (32%) Hospital Medical Staff and 19 (25%) Nurse Practitioners]. Nineteen ECGs with 4 possible answers were interpreted. Out of 1425 possible decisions 1054 (73.9%) responses were made. Only 570/1425 (40%) of the responses were correct. Diagnostic accuracy varied (0% to 78%, mean 42%±21%) across the entire cohort. Participation was high, (median 83%, IQR 50%-100%). Hospital Medical Staff had significantly higher diagnostic accuracy than nurse practitioners (50±20% vs. 38±19%, p=0.04) and Primary Care Physicians (50±20% vs. 40±21%, p=0.07) although not significant. Interactive voting systems can be rapidly and successfully used to assess ECG interpretation. Further education is necessary to improve diagnostic accuracy.

Reducing radiation exposure during transcatheter aortic valve implantation (TAVI).

OBJECTIVES: To establish radiation dose and determine the effect of changes in cine-fluoroscopic image acquisition settings on radiation dose and procedural outcomes in consecutive patients undergoing transcatheter aortic valve implantation (TAVI). BACKGROUND: The radiation dose during TAVI has not been extensively investigated. Methods to keep doses as low as reasonably achievable should be established for the safety of both the patient and the interventional team involved. METHODS: Data on radiation exposure was collected for 36 consecutive patients undergoing TAVI using standard image acquisition settings (SS) and 36 consecutive patients using modified image acquisition settings (LS). Radiation dose was recorded using an integrated dosimeter as dose area product (DAP). Data on patient characteristics, screening time, procedure time, contrast volume, and procedural outcomes were recorded prospectively. We also collected radiation dose data on 40 consecutive patients undergoing percutaneous coronary intervention in the same catheterisation laboratory. RESULTS: The median DAP for the LS group was significantly lower at 74.6 Gy*cm(2) compared to a dose of 102.4 Gy*cm(2) for the SS group (P=0.008). There were no significant differences in the screening times, procedure times, and contrast volume used. Overall, there was no difference in procedural outcomes between the two groups. The radiation dose for TAVI procedures (SS group) was comparable to PCI procedures (102.4 Gy*cm(2) vs. 94.6 Gy*cm(2) ) using the same settings in the same catheterisation laboratory. CONCLUSIONS: This study demonstrates that the radiation exposure to the patient can be significantly and simply reduced using modified dose acquisition settings for TAVI without affecting procedural outcomes.

An audit of outcomes after same-day discharge post-PCI in acute coronary syndrome and elective patients.

OBJECTIVES: To investigate the outcomes of a cohort of acute and elective percutaneous coronary intervention (PCI) patients who were discharged home 6 hours postprocedure. BACKGROUND: Contemporary PCI is safe with a low rate of acute complications. It is well established as a day procedure in elective cases; however, data are lacking in acute cases. METHODS: We describe a prospective observational audit of routine clinical practice in the 3 PCI centers in Northern Ireland. Patients were selected for same-day discharge after 6 hours of post-PCI observation. Both elective and acute coronary syndrome (ACS) cases were included. Criteria for same-day discharge were based on the technical result of the procedure rather than lesion complexity or clinical presentation. Radial access was preferred but not mandatory. Patients were contacted directly to assess for 30-day major adverse cardiovascular events (MACE). Reported events were corroborated with the general practitioner or hospital notes. RESULTS: A total of 1,059 patients were selected for same-day discharge with 30-day follow-up available for all cases. Of these, 766 (72.3%) were elective and 293 (27.7%) were ACS patients. Radial access was almost universal (98%). A total of 1,224 lesions were stented, of which 432 (40.8%) were high risk (highest risk lesion in each case by AHA/ACC classification). MACE rate at 30 days was 0.85% with a sub-acute stent thrombosis rate of 0.4%. There were no MACE events from discharge to 24 hours. CONCLUSIONS: Selected acute and elective patients with a range of lesion complexity and risk can be discharged safely home early after PCI.