Transient internal mammary artery graft stenosis on early angiography: navigating pitfalls in hybrid myocardial revascularization

OBJECTIVES

Left internal mammary artery (LIMA) graft stenoses detected at early coronary angiography may be reversible and consequently prompt unnecessary graft revision. We aim to investigate the frequency, natural course, and clinical significance of internal mammary artery graft stenosis upon early angiography in patients undergoing hybrid myocardial revascularization.

METHODS

In this retrospective sub-study of the Coronary Hybrid Revascularization Study, we compared graft appearance, ie, stenosis degree and flow, on early (in-hospital) and scheduled follow-up coronary angiography after 1 year. We assessed the change in graft patency using the Fitzgibbon classification (grade A: unimpaired runoff; grade B > 50% stenosis; grade O: occlusion), as well as graft association with adverse events (death, myocardial infarction, stroke, and repeat revascularization) at up to 5-year follow-up.

RESULTS

We report clinical follow-up data for all 131 patients included in the Coronary Hybrid Revascularization Study. Change in graft patency was analyzed in 86 patients with satisfactory visualization of the LIMA graft on early and follow-up coronary angiography. All LIMA grafts were patent at discharge and follow-up. Twenty-seven of 37 (73%) grade B graft stenoses at early angiography resolved to grade A during follow-up of median 12 months (range, 8-83 months) after surgery. Angiographically significant graft stenoses at early coronary angiography were not associated with adverse clinical outcome up to 5-year follow-up.

CONCLUSIONS

Our results suggest that the majority of clinically silent LIMA graft stenoses resolve during follow-up and are not associated with adverse clinical outcomes.

Intravascular Imaging Findings After PCI in Patients With Focal and Diffuse Coronary Artery Disease

BACKGROUND

Following percutaneous coronary intervention (PCI), optical coherence tomography provides prognosis information. The pullback pressure gradient is a novel index that discriminates focal from diffuse coronary artery disease based on fractional flow reserve pullbacks. We sought to investigate the association between coronary artery disease patterns, defined by coronary physiology, and optical coherence tomography after stent implantation in stable patients undergoing PCI.

METHODS AND RESULTS

This multicenter, prospective, single-arm study was conducted in 5 countries (NCT03782688). Subjects underwent motorized fractional flow reserve pullbacks evaluation followed by optical coherence tomography-guided PCI. Post-PCI optical coherence tomography minimum stent area, stent expansion, and the presence of suboptimal findings such as incomplete stent apposition, stent edge dissection, and irregular tissue protrusion were compared between patients with focal versus diffuse disease. Overall, 102 patients (105 vessels) were included. Fractional flow reserve before PCI was 0.65±0.14, pullback pressure gradient was 0.66±0.14, and post-PCI fractional flow reserve was 0.88±0.06. The mean minimum stent area was 5.69±1.99 mm2 and was significantly larger in vessels with focal disease (6.18±2.12 mm2 versus 5.19±1.72 mm2, P=0.01). After PCI, incomplete stent apposition, stent edge dissection, and irregular tissue protrusion were observed in 27.6%, 10.5%, and 51.4% of the cases, respectively. Vessels with focal disease at baseline had a lower prevalence of incomplete stent apposition (11.3% versus 44.2%, P=0.002) and more irregular tissue protrusion (69.8% versus 32.7%, P<0.001).

CONCLUSIONS

Baseline coronary pathophysiological patterns are associated with suboptimal imaging findings after PCI. Patients with focal disease had larger minimum stent area and a higher incidence of tissue protrusion, whereas stent malapposition was more frequent in patients with diffuse disease.

Comparison of Effect of Ischemic Postconditioning on Cardiovascular Mortality in Patients With ST-Segment Elevation Myocardial Infarction Treated With Primary Percutaneous Coronary Intervention With Versus Without Thrombectomy

In patients with ST-segment elevation myocardial infarction (STEMI), ischemic postconditioning (iPOST) have shown ambiguous results in minimizing reperfusion injury. Previous findings show beneficial effects of iPOST in patients with STEMI treated without thrombectomy. However, it remains unknown whether the cardioprotective effect of iPOST in these patients persist on long term. In the current study, all patients were identified through the DANAMI-3-iPOST database. Patients were randomized to conventional primary percutaneous coronary intervention (PCI) or iPOST in addition to PCI. Cumulative incidence rates were calculated, and multivariable analyses stratified according to thrombectomy use were performed. The primary end point was a combination of cardiovascular mortality and hospitalization for heart failure. From 2011 to 2014, 1,234 patients with STEMI were included with a median follow-up of 4.8 years. In patients treated without thrombectomy (n = 520), the primary end point occurred in 15% (48/326) in the iPOST group and in 22% (42/194) in the conventional group (unadjusted hazard ratio [HR] 0.62, 95% confidence interval [CI] 0.41 to 0.94, p = 0.023). In adjusted Cox analysis, iPOST remained associated with reduced long-term risk of cardiovascular mortality (HR 0.53, 95% CI 0.29 to 0.97, p = 0.039). In patients treated with thrombectomy (n = 714), there was no significant difference between iPOST (17%, 49/291) and conventional treatment (17%, 72/423) on the primary end point (unadjusted HR 1.01, 95% CI 0.70 to 1.45, p = 0.95). During a follow-up of nearly 5 years, iPOST reduced long-term occurrence of cardiovascular mortality and hospitalization for heart failure in patients with STEMI treated with PCI but without thrombectomy.

Association of Age With the Diagnostic Value of Coronary Artery Calcium Score for Ruling Out Coronary Stenosis in Symptomatic Patients

Importance

The diagnostic value is unclear of a 0 coronary artery calcium (CAC) score to rule out obstructive coronary artery disease (CAD) and near-term clinical events across different age groups.

Objective

To assess the diagnostic value of a CAC score of 0 for reducing the likelihood of obstructive CAD and to assess the implications of such a CAC score and obstructive CAD across different age groups.

Design, Setting, and Participants

This cohort study obtained data from the Western Denmark Heart Registry and had a median follow-up time of 4.3 years. Included patients were aged 18 years or older who underwent computed tomography angiography (CTA) between January 1, 2008, and December 31, 2017, because of symptoms that were suggestive of CAD. Data analysis was performed from April 5 to July 7, 2021.

Exposures

Obstructive CAD, which was defined as 50% or more luminal stenosis.

Main Outcomes and Measures

Proportion of individuals with obstructive CAD who had a CAC score of 0. Risk-adjusted diagnostic likelihood ratios were used to assess the diagnostic value of a CAC score of 0 for reducing the likelihood of obstructive CAD beyond clinical variables. Risk factors associated with myocardial infarction and death were estimated.

Results

A total of 23 759 symptomatic patients, of whom 12 771 (54%) had a CAC score of 0, were included. This cohort had a median (IQR) age of 58 (49-65) years and was primarily composed of women (13 160 [55%]). Overall, the prevalence of obstructive CAD was relatively low across all age groups, ranging from 3% (39 of 1278 patients) in those who were younger than 40 years to 8% (52 of 619) among those who were 70 years or older. In patients with obstructive CAD, 14% (725 of 5043) had a CAC score of 0, and the prevalence varied across age groups from 58% (39 of 68) among those who were younger than 40 years, 34% (192 of 562) among those aged 40 to 49 years, 18% (268 of 1486) among those aged 50 to 59 years, 9% (174 of 1963) among those aged 60 to 69 years, to 5% (52 of 964) among those who were 70 years or older. The added diagnostic value of a CAC score of 0 decreased at a younger age, with a risk factor-adjusted diagnostic likelihood ratio of a CAC score of 0 ranging from 0.68 (approximately 32% lower likelihood of obstructive CAD than expected) in those who were younger than 40 years to 0.18 (approximately 82% lower likelihood than expected) in those who were 70 years or older. The presence of obstructive vs nonobstructive CAD among those with a CAC score of 0 was associated with a multivariable adjusted hazard ratio of 1.51 (95% CI, 0.98-2.33) for myocardial infarction and all-cause death; however, this hazard ratio varied from 1.80 (95% CI, 1.02-3.19) in those who were younger than 60 years to 1.24 (95% CI, 0.64-2.39) in those who were 60 years or older.

Conclusions and Relevance

This cohort study found that the diagnostic value of a CAC score of 0 to rule out obstructive CAD beyond clinical variables was dependent on age, with the added diagnostic value being smaller for younger patients. In symptomatic patients who were younger than 60 years, a sizable proportion of obstructive CAD occurred among those without CAC and was associated with an increased risk of myocardial infarction and all-cause death.

Influence of Plaque Characteristics on Early Vascular Healing in Patients With ST-Elevation Myocardial Infarction

OBJECTIVES

To compare the early vascular healing of ruptured plaques (RP) and non-ruptured plaques (NRP) one month after primary percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI), using optical coherence tomography (OCT).

BACKGROUND

Vascular healing and strut coverage are important factors in reducing the risk of stent thrombosis after PCI. Influence of underlying lesion characteristics and differences in healing response between RP and NRP are unknown.

METHODS

Twenty-six STEMI-patients underwent PCI and implantation of a polymer-free drug-coated Biofreedom stent (BF-BES). OCT was performed pre-PCI, post-PCI and at 1-month follow-up. The patients were divided into two groups: RP = 15 and NRP = 11. OCT analyses of culprit lesion, post stent implantation at baseline and follow-up were performed to determine the difference in vascular healing based on presence of uncovered and/or malapposed stent struts and intraluminal filling defects.

RESULTS

The stent coverage did not differ significantly between the two groups at 1-month follow-up with percentage of uncovered struts: RP 26.5% [IQR 15.0-49.0] and NRP 28.1% [IQR 15.5-38.8] for NRP (p = 0.78). At 1-month, RP showed an increased percentage of late acquired malapposed struts (1.4% [IQR 0.8-2.4] vs. 0.0% [IQR 0.0-1.4], p = 0.03) and a larger total malapposition area (1.3 mm² [IQR 0.4-2.5] vs. 0.0 mm² [IQR 0.0-0.9], p = 0.01), compared to NRP.

CONCLUSION

Three out of four struts were covered within one month after stenting. The vascular healing was comparable in RP and NRP on stent coverage. However, RP had more and larger late acquired malapposition areas.

Long-term prognosis of patients with non-ST-segment elevation myocardial infarction according to coronary arteries atherosclerosis extent on coronary angiography: a historical cohort study

BACKGROUND

Patients with non-ST-segment elevation myocardial infarction (NSTEMI) without obstructive coronary artery disease (CAD) are often managed differently than those with obstructive CAD, therefore we aimed in this study to examine the long-term prognosis of patients with NSTEMI according to the degree of CAD on coronary angiography (CAG).

METHODS

We examined 8.889 consecutive patients admitted for first time NSTEMI during 2000-2011, to whom CAG was performed. Patients were classified by CAG into: 0-vessel disease (0VD), diffuse atherosclerosis (DA) (0% < stenosis <50%), 1-vessel disease (1VD), 2VD, and 3VD with stenosis ≥50%. Follow-up period: 13 years (median 4.5).

RESULTS

One-year mortality for NSTEMI patients with 0VD was 3.7%, DA 5.7%, 1VD 2.5%, 2VD 4.8%, and 3VD 11.5%. Non-diabetic 0VD patients had higher risk of mortality than 1VD patients (HR:1.59; 95% CI:1.21-2.02; P < 0.001), while those with diabetes mellitus (DM) had not significantly different risk. In addition 0VD group had higher risk of heart failure (HF) (HR 1.61; 95% CI: 1.39-1.88; P < 0.001), and lower risk of recurrent MI (HR:0.55; 95% CI:0.39-0.77; P < 0.001) compared with 1VD. For patients with DA; mortality and HF risks were higher than 1VD and not different than 2VD, while recurrent MI risk was not different than 1VD and lower than 2VD. Finally, the DA group had higher risk of mortality if they had DM, higher risk of recurrent MI, and not different risk of HF and stroke compared with the 0VD group patients.

CONCLUSION

Patients with NSTEMI and non-obstructive CAD (both normal coronaries and diffuse atherosclerosis) have a comparable prognosis to patients with one- or two-vessel disease. Patients with diffuse atherosclerosis have worse prognosis than those with angiographically normal coronary arteries.

Myocardial Perfusion Imaging Versus Computed Tomography Angiography-Derived Fractional Flow Reserve Testing in Stable Patients With Intermediate-Range Coronary Lesions: Influence on Downstream Diagnostic Workflows and Invasive Angiography Findings

Background

Data on the clinical utility of coronary computed tomography angiography–derived fractional flow reserve (FFR_CT) are sparse. In patients with intermediate (40–70%) coronary stenosis determined by coronary computed tomography angiography, we investigated the association of replacing standard myocardial perfusion imaging with FFR_CT testing with downstream utilization of invasive coronary angiography (ICA) and the diagnostic yield of ICA (rate of no obstructive disease, and rate of revascularization).

Methods and Results

This was a single‐center observational study of symptomatic patients with suspected coronary artery disease referred to coronary computed tomography angiography between 2013 and 2015. Patients were divided into 3 historical groups based on the adjunctive functional testing approach: myocardial perfusion imaging (n=1332) or FFR_CT “implementation” (n=800) or “clinical use” (n=1391). Propensity score matching was used to estimate the average period effect on outcomes. Patients in the FFR_CT clinical use group versus the myocardial perfusion imaging group were older and had higher pretest probability of obstructive disease. After adjusting for baseline risk characteristics, there was a reduction in downstream ICA utilization (absolute risk difference: −4.2; 95% CI, −6.9 to −1.6; P=0.002). In patients referred to ICA, findings of no obstructive coronary artery disease decreased (−12.8%; 95% CI, −22.2 to −3.4; P=0.008) and rate of coronary revascularization increased (14.1%; 95% CI, 3.3–24.9; P=0.01), as did availability of functional information for guidance of revascularization (27.8%; 95% CI, 11.3–44.4; P<0.001) after clinical adoption of FFR_CT.

Conclusions

Replacing adjunctive myocardial perfusion imaging with FFR_CT testing for functional assessment of intermediate stenosis determined by coronary computed tomography angiography in stable coronary artery disease was associated with less ICA utilization, and a higher ICA diagnostic yield. The findings in this observational study needs confirmation in prospective, randomized trials.

Clinical Use of Coronary CTA-Derived FFR for Decision-Making in Stable CAD

OBJECTIVES

The goal of this study was to assess the real-world clinical utility of fractional flow reserve (FFR) derived from coronary computed tomography angiography (FFR_CT) for decision-making in patients with stable coronary artery disease (CAD).

BACKGROUND

FFR_CT has shown promising results in identifying lesion-specific ischemia. The real-world feasibility and influence on the diagnostic work-up of FFR_CT testing in patients suspected of having CAD are unknown.

METHODS

We reviewed the complete diagnostic work-up of nonemergent patients referred for coronary computed tomography angiography over a 12-month period at Aarhus University Hospital, Denmark, including all patients with new-onset chest pain with no known CAD and with intermediate-range coronary lesions (lumen reduction, 30% to 70%) referred for FFR_CT. The study evaluated the consequences on downstream diagnostic testing, the agreement between FFR_CT and invasively measured FFR or instantaneous wave-free ratio (iFR), and the short-term clinical outcome after FFR_CT testing.

RESULTS

Among 1,248 patients referred for computed tomography angiography, 189 patients (mean age 59 years; 59% male) were referred for FFR_CT, with a conclusive FFR_CT result obtained in 185 (98%). FFR_CT was ≤0.80 in 31% of patients and 10% of vessels. After FFR_CT testing, invasive angiography was performed in 29%, with FFR measured in 19% and iFR in 1% of patients (with a tendency toward declining FFR-iFR guidance during the study period). FFR_CT ≤0.80 correctly classified 73% (27 of 37) of patients and 70% (37 of 53) of vessels using FFR ≤0.80 or iFR ≤0.90 as the reference standard. In patients with FFR_CT >0.80 being deferred from invasive coronary angiography, no adverse cardiac events occurred during a median follow-up period of 12 (range 6 to 18 months) months.

CONCLUSIONS

FFR_CT testing is feasible in real-world symptomatic patients with intermediate-range stenosis determined by coronary computed tomography angiography. Implementation of FFR_CT for clinical decision-making may influence the downstream diagnostic workflow of patients. Patients with an FFR_CT value >0.80 being deferred from invasive coronary angiography have a favorable short-term prognosis.

Feasibility and early safety of hybrid coronary revascularisation combining off-pump coronary surgery through J-hemisternotomy with percutaneous coronary intervention

AIMS

To assess the procedural feasibility and early safety of hybrid coronary revascularisation, combining off-pump left internal mammary artery grafting to the left descending coronary artery (LAD) through an inferior J-hemisternotomy (JOPCAB) with percutaneous coronary intervention (PCI) of non-LAD lesions.

METHODS AND RESULTS

A total of 100 patients with multivessel coronary artery disease involving LAD were included in this prospective registry. Hybrid revascularisation was performed by JOPCAB, either prior to PCI (89%) or following PCI (11%). In 96% of the cases, the procedure was carried out according to the preoperative strategy and without perioperative (24 hours) major adverse cardiac or cerebral events. At one month, we observed no deaths, one stroke and two procedure-related myocardial infarctions. Five patients underwent reoperation for graft dysfunction, four of whom were identified by angiography without prior signs of ischaemia. Reoperation due to bleeding was necessary in six patients, and nine patients received red blood cell transfusion.

CONCLUSIONS

Our prospective registry documented promising procedural feasibility and early safety of coronary hybrid revascularisation combining JOPCAB with PCI. ClinicalTrials.gov identifier: NCT01496664.

Assessment of central blood pressure in patients with type 2 diabetes: a comparison between SphygmoCor and invasively measured values

BACKGROUND

The SphygmoCor is used for noninvasive assessment of ascending aortic blood pressure (BP). However, the validity of the SphygmoCor transfer function has not been tested in an exclusively type 2 diabetic patient sample. Calibration with systolic (SBP) and diastolic (DBP) brachial BP has previously been associated with substantial imprecision of central BP estimates. We hypothesized that different noninvasive calibration strategies might improve the accuracy of the estimated ascending aortic BPs.

METHODS

In 34 patients with type 2 diabetes we estimated ascending aortic SBP and DBP using the SphygmoCor device and compared these data with invasively recorded data. The validity of the transfer function was assessed by calibrating with invasively recorded DBP and mean BP (MBP). The influence of noninvasive calibration strategies was assessed by calibrating with brachial oscillometric SBP+DBP vs. DBP+MBP using a form factor (ff) of 0.33 and 0.40, respectively.

RESULTS

When calibrating with invasive BP, the difference between estimated and invasively measured ascending aortic SBP and DBP was -2.3±5.6/1.0±0.9 mm Hg. When calibrating with oscillometric brachial BPs, the differences were -9.6±8.1/14.1±6.2 mm Hg (calibration with SBP and DBP), -8.3±11.7/13.9±6.1 mm Hg (DBP and MBP; ff = 0.33), and 1.9±12.2/14.1±6.2 mm Hg (DBP and MBP; ff = 0.40), respectively. Calibration with the average of 3 brachial BPs did not improve accuracy.

CONCLUSIONS

The SphygmoCor transfer function seems valid in patients with type 2 diabetes. Noninvasive calibration with DBP and MBP (ff = 0.40) enables accurate estimation of mean ascending aortic SBP at the group level. However, the wide limits of agreement indicate limited accuracy in the individual patient.

CLINICAL TRIALS REGISTRATION

Clinical Trials No. NCT01538290.

Event detection using population-based health care databases in randomized clinical trials: a novel research tool in interventional cardiology

AIM

To describe a new research tool, designed to reflect routine clinical practice and relying on population-based health care databases to detect clinical events in randomized clinical trials.

BACKGROUND

Randomized clinical trials often focus on short-term efficacy and safety in a controlled environment. Trial follow-up may be linked with study-related investigations and differ from routine clinical practice. Because treatment and control in randomized trials differ from daily practice, trial results may have reduced general applicability and may be of limited value in clinical decision-making. Further, it is economically very costly to conduct randomized clinical trials.

METHODS AND RESULTS

Population-based health care databases collect data continuously and prospectively, and make it possible to monitor lifelong outcomes of cardiac interventions in large numbers of patients. This strengthens external validity by eliminating the effects of study-related monitoring or diagnostic tests. Further, follow-up data can be obtained at low expense. Importantly, data sources encompassing a complete population are likely to reflect clinical practice. Because population-based health care databases collect data for quality-control and administrative purposes unrelated to scientific investigations, certain biases, such as nonresponse bias, recall bias, and bias from losses to follow-up, can be avoided.

CONCLUSION

Event detection using population-based health care databases is a new research tool in interventional cardiology that may allow large, low-cost, randomized clinical trials to reflect daily clinical practice, covering a broad range of patients and end points with complete lifelong follow-up.