Continuous thermodilution and microvascular resistance reserve during the index procedure in acute coronary syndrome without obstructive coronary artery disease: A pilot study.

BACKGROUND: In 5%-25% of non-ST-elevation acute coronary syndrome (NSTE-ACS) patients, coronary angiography reveals no obstructive coronary arteries (MINOCA). Coronary microvascular disease (CMD) is a potential causal pathophysiological mechanism in these patients and can be diagnosed by continuous thermodilution assessment. Recently, the microvascular resistance reserve (MRR) has been introduced as a novel index to assess the vasodilatory capacity of the microcirculation. However, continuous thermodilution and MRR have never been investigated in the acute setting in MINOCA patients and invasive assessment of the microcirculation in these patients are currently lacking. AIMS: The objectives of the study were to investigate the incidence of CMD (MRR ≤ 2.7) in patients with MINOCA and to evaluate the feasibility and safety of continuous thermodilution-based assessment during index coronary angiography in the acute setting. METHODS: This study was a prospective, observational, pilot study investigating coronary physiology in the acute setting in MINOCA patients. Patients admitted with a diagnosis of NSTE-ACS were eligible for inclusion. RESULTS: In total, 19 MINOCA patients were included in this analysis; the mean age was 70 ± 9 years, and 79% were females. CMD was present in 6 patients (32%). Qrest was significantly higher in the MRR ≤ 2.7 group compared to the MRR > 2.7 group (0.076 [0.057-0.100] vs. 0.049 [0.044-0.071] L/min, p = 0.03). Rµ,rest was significantly lower in the MRR ≤ 2.7 group compared to the MRR > 2.7 group (1083 [710-1510] vs. 1563 [1298-1970] WU, p = 0.04). No periprocedural complications or hemodynamic instability have occurred during continuous thermodilution assessment during the index coronary angiography. CONCLUSION: In patients admitted for MINOCA undergoing immediate coronary angiography, continuous thermodilution assessment and MRR are feasible and safe in the acute setting, and evidence of functional CMD could be observed in one-third of the MINOCA patients.

Impact of symptom duration and mechanical circulatory support on prognosis in cardiogenic shock complicating acute myocardial infarction.

BACKGROUND: Mortality rates in patients with cardiogenic shock complicating acute myocardial infarction (AMICS) remain high despite advancements in AMI care. Our study aimed to investigate the impact of prehospital symptom duration on the prognosis of AMICS patients and those receiving mechanical circulatory support (MCS). METHODS AND RESULTS: We conducted a retrospective cohort study with data registered in the Netherlands Heart Registration. A total of 1,363 patients with AMICS who underwent percutaneous coronary intervention between 2017 and 2021 were included. Patients presenting after out-of-hospital cardiac arrest were excluded. Most patients were male (68%), with a median age of 69 years (IQR 61-77), predominantly presenting with ST-elevation myocardial infarction (86%). The overall 30-day mortality was 32%. Longer prehospital symptom duration was associated with a higher 30-day mortality with the following rates: < 3 h, 26%; 3-6 h, 29%; 6-24 h, 36%; ≥ 24 h, 46%; p < 0.001. In a subpopulation of AMICS patients with MCS (n = 332, 24%), symptom duration of > 24 h was associated with significantly higher mortality compared to symptom duration of < 24 h (59% vs 45%, p = 0.029). Multivariate analysis identified > 24 h symptom duration, age and in-hospital cardiac arrest as predictors of 30-day mortality in MCS patients. CONCLUSION: Prolonged prehospital symptom duration was associated with significantly increased 30-day mortality in patients presenting with AMICS. In AMICS patients treated with MCS, a symptom duration of > 24 h was an independent predictor of poor survival. These results emphasise the critical role of early recognition and intervention in the prognosis of AMICS patients.

Bifurcation PCI with a hybrid strategy with drug- eluting balloons versus a stepwise provisional two- stent strategy: Rationale and design of the hybrid DEB study.

The optimal treatment strategy for coronary bifurcation lesions by percutaneous coronary intervention (PCI) is complex and remains a subject of debate. Current guidelines advise a stepwise provisional approach with optional two-stent strategy. However, a two-stent strategy, both upfront and stepwise provisional, is technically demanding. Therefore, there is increasing interest in the use of drug-eluting balloons (DEB) in bifurcation lesions, mainly after a provisional approach with unsatisfactory result of the side branch. Some small pilot studies already showed that the use of DEB in bifurcation lesions is safe and feasible. However, a randomized comparison of this hybrid DEB strategy with a two-stent strategy is currently lacking. TRIAL DESIGN: The Hybrid DEB study is a prospective, multicenter, randomized controlled trial investigating noninferiority of a hybrid DEB approach, using a combination of a drug-eluting stent (DES) in the main vessel and DEB in the side branch, compared to stepwise provisional two-stent strategy in patients with true bifurcation lesions. A total of 500 patients with de novo true coronary bifurcation lesions, treated with a stepwise provisional approach and an unsatisfactory result of the side branch after main vessel stenting (≥ 70% stenosis and/or < thrombolysis in myocardial infarction III flow), will be randomized in a 1:1 ratio to receive either treatment with a DEB or with a DES in the side branch. The primary endpoint is a composite endpoint of the occurrence of all-cause death, periprocedural or spontaneous myocardial infarction and/or target vessel revascularization at the anticipated median 2-year follow-up. CONCLUSION: The Hybrid DEB study will compare in a multicenter, randomized fashion a hybrid DEB approach with a stepwise provisional two-stent strategy in patients with true bifurcation lesions. TRIAL REGISTRATION: ClinicalTrials.gov no. NCT05731687.

Angiographic predictors of aberrant circumflex artery during cardiac catheterization.

OBJECTIVES: To identify angiographic predictors of aberrant left circumflex artery (LCx) by comparing left main (LM) length and bifurcation angle between patients with aberrant LCx and normal anatomy. BACKGROUND: Failure to recognize aberrant LCx during a cardiac catheterization may hamper correct diagnosis, delay intervention in acute coronary syndromes, and result in increased contrast volume, radiation exposure, and infarct size. METHODS: We retrospectively analyzed angiograms of aberrant LCx patients and normal anatomy matched controls, in three-participating centers. LM-length, bifurcation angle between the left anterior descending (LAD) and the first non-LAD branch of the LM, and procedural data were compared. RESULTS: Between 2003 and 2020, 136 patients with aberrant LCx and 135 controls were identified. More catheters (2.4 ± 0.6 vs. 2.2 ± 0.9, p = 0.009), larger contrast volumes (169 ± 94 ml vs. 129 ± 68 ml, p < 0.0005), and prolonged fluoroscopy time (652.9 ± 623.7 s vs. 393.1 ± 332.1 s, p < 0.0005), were required in the aberrant LCx-group compared with controls. Patients with aberrant LCx had a longer LM-length and a more acute bifurcation angle, both in caudal and cranial views, compared with controls (24.7 ± 8.1 vs. 10.8 ± 4.5 mm, p < 0.0005 and 26.7 ± 7.4 vs. 12 ± 5.5 mm, p < 0.0005, respectively, and 45.2° ± 12° vs. 88.8° ± 23°, p < 0.0005 and 51.9° ± 21° vs. 68.2° ± 28.3°, p < 0.0005, respectively). In ROC analysis, LM-length showed the best diagnostic accuracy for detecting aberrant LCx. In multiple logistic regression analysis, a cranially measured LM-length > 17.7 mm was associated with a 5.3 times greater probability of predicting aberrant LCx [95% CI (3.4-8.1), p < 0.0001]. CONCLUSIONS: Our study suggests that a long LM-length and an acute bifurcation angle can indicate the presence of aberrant LCx. We present a practical algorithm for its rapid identification.

Thermodilution-Based Invasive Assessment of Absolute Coronary Blood Flow and Microvascular Resistance: Quantification of Microvascular (Dys)Function?

During the last two decades, there has been a sharp increase in both interest and knowledge about the coronary microcirculation. Since these small vessels are not visible by the human eye, physiologic measurements should be used to characterize their function. The invasive methods presently used (coronary flow reserve (CFR) and index of microvascular resistance (IMR)) are operator-dependent and mandate the use of adenosine to induce hyperemia. In recent years, a new thermodilution-based method for measurement of absolute coronary blood flow and microvascular resistance has been proposed and initial procedural problems have been overcome. Presently, the technique is easy to perform using the Rayflow infusion catheter and the Coroventis software. The method is accurate, reproducible, and completely operator-independent. This method has been validated noninvasively against the current golden standard for flow assessment: Positron Emission Tomography-Computed Tomography (PET-CT). In addition, absolute flow and resistance measurements have proved to be safe, both periprocedurally and at long-term follow-up. With an increasing number of studies being performed, this method has great potential for better understanding and quantification of microvascular disease.

Angiographic and clinical outcomes of antegrade versus retrograde techniques for chronic total occlusion revascularizations: Insights from the PRISON IV trial.

OBJECTIVES: Available data indicate mixed outcomes after using retrograde techniques for chronic total occlusion(CTO) recanalization, with generally higher need for repeat revascularization. Aim of this study is to analyze the angiographic and clinical outcome of patients treated with retrograde techniques in the PRISON-IV trial. METHODS AND RESULTS: This is a post-hoc sub-analysis from the randomized PRISON-IV trial. Briefly, 330 patients with a successfully recanalized CTO lesion were randomized 1:1 to receive either hybrid-SES or EES. The hybrid-SES failed to reach the non-inferiority primary endpoint of in-segment late lumen loss at 9-month angiography follow-up. In the present analysis, we divided the population according to the first technical approach, namely antegrade (n = 285) or retrograde approach (n = 45). Demographic characteristics were similar between the two groups, while angiographic features disclosed higher CTO lesion complexity in the group treated with retrograde techniques (J-CTO score: 1.8 ± 1.1 vs 2.6 ± 1.1, respectively, P < 0.001), with longer occlusions (17.6 ± 10 mm vs 28.8 ± 18.7 mm, P < 0.001) and longer stented segment (48.9 ± 24.4 mm vs 73.1 ± 33.2 mm, P < 0.001). Quantitative coronary analysis disclosed similar results at follow-up angiography, with a non-significantly higher in-stent late-lumen loss in the retrograde group (0.08 ± 0.52 mm vs 0.18 ± 0.56 mm, P = 0.32). Clinical follow-up at 12-months showed similar outcome, with a non-significantly higher target-lesions revascularization rate in the retrograde group (6% vs 11.1% respectively, P = 0.2). Significant improvements in angina functional class were observed in both groups. CONCLUSIONS: The present analysis supports the benefits of retrograde techniques in CTO revascularization, with non-significant differences in angiographic and clinical outcomes at late follow-up.

Impact of ultra-thin struts on restenosis after chronic total occlusion recanalization: Insights from the randomized PRISON IV trial.

OBJECTIVES: The PRISON-IV trial showed inferior outcome in patients with chronic total occlusions (CTOs) treated with the ultrathin-struts (60 µm for stent diameter ≤3 mm, 81µm >3 mm) hybrid-sirolimus eluting stents (SES) compared with everolimus eluting stents (EES, 81 µm). The aim of this study is to investigate if the use of smaller stents (≤3 mm) was responsible for the inferior outcome reported in the trial. METHODS: In the PRISON-IV trial 330 patients with CTO lesion were randomized 1:1 to receive either hybrid-SES or EES. The hybrid-SES failed to reach the non-inferiority primary endpoint of in-segment late lumen loss (LLL) at 9-month angiographic follow-up. In this sub-analysis, we divided the population according to the different size of stents implanted in those receiving only stents with diameter ≤3 mm (Group-A, 178 patients), only stents >3 mm (Group-B, 59 patients), and those receiving stents of both sizes (Group-C, 93 patients). RESULTS: Baseline and procedural characteristics were comparable in the three groups. At angiographic follow-up, most of the adverse outcomes occurred in Group A, with higher incidence of binary restenosis in the Hybrid-SES versus EES (10.3% vs 1.3%, P = 0.03) and augmented in-stent diameter stenosis (26.04 ± 18.59% vs 21.24 ± 12.84, P = 0.06). Similarly, optical coherence tomography (OCT), which was performed in 60 patients at follow-up, documented a mild trend toward lower values of minimum in stent area in Hybrid-SES arm of Group A (4.4 ± 1.02mm2 vs 5.0 ± 1.28mm2, respectively, P = 0.16). CONCLUSIONS: The present analysis suggests that the inferior performance of the ultra-thin hybrid-SES in CTO-PCI is particularly pronounced when smaller stent (≤3 mm diameter) are adopted, if compared with EES.

Fluid-filled versus sensor-tipped pressure guidewires for FFR and Pd/Pa measurement; PW-COMPARE study.

BACKGROUND: Fluid-filled pressure guidewires are unaffected by the previously inevitable hydrostatic pressure gradient (HPG). This study aimed to compare simultaneous pressure measurements with fluid-filled and sensor-tipped pressure guidewires. METHODS: Fifty patients underwent fractional flow reserve (FFR) and Pd/Pa measurement with a fluid-filled and a sensor-tipped pressure guidewire simultaneously. To assess maneuverability, patients were randomized with respect to which pressure guidewire was used to cross the lesion first. Lateral fluoroscopy was used to estimate height difference between catheter tip and distal wire position (and thus HPG). Agreement between pressure measurements was studied. RESULTS: Measurements were performed in LM (4% (n = 2)), LAD (44% (n = 22)), LCX (26% (n = 13)), and RCA (26% (n = 13)). Simultaneous pressure measurements showed excellent agreement (mean FFR difference - 0.01 ± 0.03 (r = 0.959, p < 0.001), mean Pd/Pa difference - 0.01 ± 0.04 (r = 0.929, p < 0.001)). FFR was ≤0.80 in 42.6% (n = 20) with fluid-filled FFR measurements versus 46.8% (n = 22) by sensor-tipped FFR measurements. Mean height difference was 15 ± 34 mm, and strongly dependent on the coronary artery (LAD 45 ± 10 mm, LCX -23 ± 16 mm, RCA -13 ± 17 mm). There was a strong correlation between height difference and difference in pressure ratios between sensor-tipped and fluid-filled pressure guidewires (FFR r = -0.850, p < 0.001; Pd/Par = -0.641, p < 0.001). Largest FFR differences were present in the LAD (-0.04 ± 0.02). After HPG correction, mean difference between HPG-corrected sensor-tipped FFR and fluid-filled FFR was 0.00 ± 0.02, mean Pd/Pa difference was 0.01 ± 0.03. CONCLUSIONS: This study shows excellent overall correlation between FFR and Pd/Pa measurements with both pressure guidewires. Differences measured with fluid-filled and sensor-tipped pressure guidewires are vessel-specific and attributable to hydrostatic pressure gradients (NCT04802681).

Characteristics and Outcome in Cardiogenic Shock according to Vascular Access Site for PCI.

BACKGROUND: The optimal vascular access site for percutaneous coronary interventions (PCI) in patients with acute myocardial infarction (AMI) complicated by cardiogenic shock (CS) remains uncertain. While observational data favor transradial access (TRA) due to lower complication rates and mortality, transfemoral (TFA) PCI offers advantages such as shorter access and procedure times, along with quicker escalation to mechanical circulatory support (MCS). In this study, we aimed to investigate factors associated with a transfemoral approach and compare mortality rates between TRA and TFA in AMI-CS patients undergoing PCI. METHODS: Data from a nationwide registry of AMI-CS patients undergoing PCI (2017-2021) were analyzed. We compared patient demographics, procedural details, and outcomes between TRA and TFA groups. Logistic regression identified access site factors and radial-to-femoral cross-over predictors. Propensity score matched (PSM) analysis examined the impact of access site on mortality. RESULTS: Of 1562 patients, 45% underwent TRA PCI, with an increasing trend over time. TFA patients were more often female, had a history of coronary artery bypass grafting (CABG), lower blood pressure, higher resuscitation and intubation rates, and elevated lactate levels. After PSM, 30-day mortality was lower in TRA (33% vs. 46%, p <0.001). Predictors for cross-over included left coronary artery interventions, multivessel PCI, and MCS initiation. CONCLUSION: Significant differences exist between TRA and TFA PCI in AMI-CS. TFA was more common in patients with worse hemodynamics and was associated with higher 30-day mortality compared to TRA. This mortality difference persisted in the propensity score matched analysis.

Prehospital risk assessment and direct transfer to a percutaneous coronary intervention centre in suspected acute coronary syndrome.

OBJECTIVE: Prehospital risk stratification and triage are currently not performed in patients suspected of non-ST-segment elevation acute coronary syndrome (NSTE-ACS). This may lead to prolonged time to revascularisation, increased duration of hospital admission and higher healthcare costs. The preHEART score (prehospital history, ECG, age, risk factors and point-of-care troponin score) can be used by emergency medical services (EMS) personnel for prehospital risk stratification and triage decisions in patients with NSTE-ACS. The aim of the current study was to evaluate the effect of prehospital risk stratification and direct transfer to a percutaneous coronary intervention (PCI) centre, based on the preHEART score, on time to final invasive diagnostics or culprit revascularisation. METHODS: Prospective, multicentre, two-cohort study in patients with suspected NSTE-ACS. The first cohort is observational (standard care), while the second (interventional) cohort includes patients who are stratified for direct transfer to either a PCI or a non-PCI centre based on their preHEART score. Risk stratification and triage are performed by EMS personnel. The primary endpoint of the study is time from first medical contact until final invasive diagnostics or revascularisation. Secondary endpoints are time from first medical contact until intracoronary angiography (ICA), duration of hospital admission, number of invasive diagnostics, number of inter-hospital transfers and major adverse cardiac events at 7 and 30 days. RESULTS: A total of 1069 patients were included. In the interventional cohort (n=577), time between final invasive diagnostics or revascularisation (42 (17-101) hours vs 20 (5-44) hours, p<0.001) and length of hospital admission (3 (2-5) days vs 2 (1-4) days, p=0.007) were shorter than in the observational cohort (n=492). In patients with NSTE-ACS in need for ICA or revascularisation, healthcare costs were reduced in the interventional cohort (€5599 (2978-9625) vs €4899 (2278-5947), p=0.02). CONCLUSION: Prehospital risk stratification and direct transfer to a PCI centre, based on the preHEART score, reduces time from first medical contact to final invasive diagnostics and revascularisation, reduces duration of hospital admission and decreases healthcare costs in patients with NSTE-ACS in need for ICA or revascularisation. TRIAL REGISTRATION: NCT05243485.

A randomised trial of selective intracoronary hypothermia during primary PCI.

BACKGROUND: While experimental data suggest that selective intracoronary hypothermia decreases infarct size, studies in patients with ST-elevation myocardial infarction (STEMI) are lacking. AIMS: We investigated the efficacy of selective intracoronary hypothermia during primary percutaneous coronary intervention (PCI) to decrease infarct size in patients with STEMI. METHODS: In this multicentre randomised controlled trial, 200 patients with large anterior wall STEMI were randomised 1:1 to selective intracoronary hypothermia during primary PCI or primary PCI alone. Using an over-the-wire balloon catheter for infusion of cold saline and a pressure-temperature wire to monitor the intracoronary temperature, the anterior myocardium distal to the occlusion was selectively cooled to 30-33°C for 7-10 minutes before reperfusion (occlusion phase), immediately followed by 10 minutes of cooling after reperfusion (reperfusion phase). The primary endpoint was infarct size as a percentage of left ventricular mass on cardiovascular magnetic resonance imaging after 3 months. RESULTS: Selective intracoronary hypothermia was performed in 94/100 patients randomised to cooling. Distal coronary temperature decreased by 6°C within 43 seconds (interquartile range [IQR] 18-113). The median duration of the occlusion phase and reperfusion phase were 8.2 minutes (IQR 7.2-9.0) and 9.1 minutes (IQR 8.2-10.0), respectively. The infarct size at 3 months was 23.1±12.5% in the selective intracoronary hypothermia group and 21.6±12.2% in the primary PCI alone group (p=0.43). The left ventricular ejection fraction at 3 months in each group were 49.1±10.2% and 50.1±10.4%, respectively (p=0.53). CONCLUSIONS: Selective intracoronary hypothermia during primary PCI in patients with anterior wall STEMI was feasible and safe but did not decrease infarct size compared with standard primary PCI. (ClinicalTrials.gov: NCT03447834).

Ultrasound-guided versus fluoroscopy-guided large-bore femoral access in PCI of complex coronary lesions: the international, multicentre, randomised ULTRACOLOR Trial.

BACKGROUND: Transfemoral access is often used when large-bore guide catheters are required for percutaneous coronary intervention (PCI) of complex coronary lesions, especially when large-bore transradial access is contraindicated. Whether the risk of access site complications for these procedures may be reduced by ultrasound-guided puncture is unclear. AIMS: We aimed to show the superiority of ultrasound-guided femoral puncture compared to fluoroscopy-guided access in large-bore complex PCI with regard to access site-related Bleeding Academic Research Consortium 2, 3 or 5 bleeding and/or vascular complications requiring intervention during hospitalisation. METHODS: The ULTRACOLOR Trial is an international, multicentre, randomised controlled trial investigating whether ultrasound-guided large-bore femoral access reduces clinically relevant access site complications compared to fluoroscopy-guided large-bore femoral access in PCI of complex coronary lesions. RESULTS: A total of 544 patients undergoing complex PCI mandating large-bore (≥7 Fr) transfemoral access were randomised at 10 European centres (median age 71; 76% male). Of these patients, 68% required PCI of a chronic total occlusion. The primary endpoint was met in 18.9% of PCI with fluoroscopy-guided access and 15.7% of PCI with ultrasound-guided access (p=0.32). First-pass puncture success was 92% for ultrasound-guided access versus 85% for fluoroscopy-guided access (p=0.02). The median time in the catheterisation laboratory was 102 minutes versus 105 minutes (p=0.43), and the major adverse cardiovascular event rate at 1 month was 4.1% for fluoroscopy-guided access and 2.6% for ultrasound-guided access (p=0.32). CONCLUSIONS: As compared to fluoroscopy-guided access, the routine use of ultrasound-guided access for large-bore transfemoral complex PCI did not significantly reduce clinically relevant bleeding or vascular access site complications. A significantly higher first-pass puncture success rate was demonstrated for ultrasound-guided access. CLINICALTRIALS: gov identifier: NCT04837404.

Neuromodulation in patients with refractory angina pectoris: a review.

The number of patients with coronary artery disease (CAD) who have persisting angina pectoris despite optimal medical treatment known as refractory angina pectoris (RAP) is growing. Current estimates indicate that 5-10% of patients with stable CAD have RAP. In absolute numbers, there are 50 000-100 000 new cases of RAP each year in the USA and 30 000-50 000 new cases each year in Europe. The term RAP was formulated in 2002. RAP is defined as a chronic disease (more than 3 months) characterized by diffuse CAD in the presence of proven ischaemia which is not amendable to a combination of medical therapy, angioplasty, or coronary bypass surgery. There are currently few treatment options for patients with RAP. One such last-resort treatment option is spinal cord stimulation (SCS) with a Class of recommendation IIB, level of evidence B in the 2019 European Society of Cardiology guidelines for the diagnosis and management of chronic coronary syndromes. The aim of this review is to give an overview of neuromodulation as treatment modality for patients with RAP. A comprehensive overview is given on the history, proposed mechanism of action, safety, efficacy, and current use of SCS.

Results of systematic patient outcome monitoring: Does post-dilatation during angiography-guided percutaneous coronary intervention improve clinical outcomes?

OBJECTIVES: This study evaluates clinical outcomes after implementing a liberal post-dilatation strategy during PCI. BACKGROUND: Post-dilatation after percutaneous coronary intervention (PCI) is performed to achieve optimal stent expansion and reduce complications. However, its prognostic effects are unclear and conflicting. METHODS: This study is a pre-post-intervention analysis of two cohorts, before (2015-2017) and after (2018-2020) implementation of a liberal post-dilatation strategy. The primary end point consisted of major adverse cardiovascular events (MACE) at 30 days. Secondary end points consisted of the individual components of the primary end point as well as 1 year mortality and target vessel revascularization. RESULTS: A total of 10,153 patients were included: 5,383 in the pre-cohort and 4,770 in the post-cohort. The 30-day MACE was 5.00% in the pre-cohort and 4.09% in the post-cohort (p = 0.008; OR 0.75 (CI 0.61-0.93)). There was a significant difference between the pre- and post-cohort in 30-day mortality, respectively, 2.91% and 2.25% (p = .01; OR 0.70 (CI 0.53-0.93)), and MI at 30 days, 1.17% versus 0.59% (p = .003; OR 0.49 (CI 0.31-0.78)). At 1 year, there was a significant difference in mortality between the pre-cohort, 5.84%, and post-cohort, 5.19% (p = .02; OR 0.79 (CI 0.66-0.96)). CONCLUSIONS: A liberal post-dilatation strategy after PCI was associated with a significant decrease in 30-day MACE, 30-day MI, 30-day mortality, and 1-year mortality. Future studies are warranted to validate the causality between post-dilatation and improvement of clinical outcomes.

Changes in absolute flow, myocardial resistance and FFR after chronic total occlusion percutaneous coronary intervention.

BACKGROUND: Randomised studies of percutaneous coronary intervention (PCI) in patients with chronic total occlusion (CTO) have shown inconsistent outcomes, suggesting incomplete understanding of this cohort and their coronary physiology. To address this shortcoming, we designed a prospective observational study to measure the recovery of absolute coronary blood flow following successful CTO PCI Aims: We sought to identify patient and procedural characteristics associated with a favourable physiological outcome after CTO PCI. METHODS: Consecutive patients with a CTO subtending viable myocardium underwent PCI utilising contemporary techniques and the hybrid algorithm. Immediately after PCI, and at 3-month follow-up, physiological measurements were performed utilising continuous thermodilution. RESULTS: A total of 81 patients were included with a mean age of 63.6±8.9 years, and 66 (81.5%) were male. Physiological measurements of absolute coronary blood flow in the CTO vessel increased by 30% (p<0.001) and microvascular resistance reduced by 16% (p<0.001) from immediately post-CTO PCI to follow-up assessment. Fractional flow reserve increased by 0.02 (p=0.015) in the same period. Prior coronary artery bypass graft (CABG) and a higher estimated glomerular filtration rate (eGFR) were associated with a larger change in absolute flow. An extraplaque strategy was associated with a smaller change in absolute flow. CONCLUSIONS: Post-CTO PCI, there is a continued augmentation in absolute coronary blood flow and reduction in microvascular resistance from baseline to follow-up at 3 months. Prior CABG and a higher baseline eGFR were predictors of a larger change in absolute coronary flow, whilst an extraplaque final wire path strategy predicted a smaller change. Lastly, the patient characteristics and comorbidities had a larger influence than procedural factors on the observed change in absolute flow.

Characteristics, Treatment Strategies and Outcome in Cardiogenic Shock Complicating Acute Myocardial Infarction: A Contemporary Dutch Cohort.

Cardiogenic shock (CS) complicating acute myocardial infarction (AMI) is associated with high morbidity and mortality. Our study aimed to gain insights into patient characteristics, outcomes and treatment strategies in CS patients. Patients with CS who underwent percutaneous coronary intervention (PCI) between 2017 and 2021 were identified in a nationwide registry. Data on medical history, laboratory values, angiographic features and outcomes were retrospectively assessed. A total of 2328 patients with a mean age of 66 years and of whom 73% were male, were included. Mortality at 30 days was 39% for the entire cohort. Non-survivors presented with a lower mean blood pressure and increased heart rate, blood lactate and blood glucose levels (p-value for all <0.001). Also, an increased prevalence of diabetes, multivessel coronary artery disease and a prior coronary event were found. Of all patients, 24% received mechanical circulatory support, of which the majority was via intra-aortic balloon pumps (IABPs). Furthermore, 79% of patients were treated with at least one vasoactive agent, and multivessel PCI was performed in 28%. In conclusion, a large set of hemodynamic, biochemical and patient-related characteristics was identified to be associated with mortality. Interestingly, multivessel PCI and IABPs were frequently applied despite a lack of evidence.

Changes in coronary collateral function after successful chronic total occlusion percutaneous coronary intervention.

BACKGROUND: Contemporary chronic total occlusion (CTO) percutaneous coronary intervention (PCI) incorporates wire escalation and dissection/re-entry recanalisation strategies. AIMS: The purpose of the study was to investigate changes in collateral function after CTO PCI and to identify whether the mode of successful recanalisation influences collateral function regression. METHODS: Patients scheduled for elective CTO PCI with evidence of viability in the CTO territory by noninvasive imaging were included in this study. After successful CTO PCI, the aortic pressure (Pa) and distal coronary artery wedge pressure (Pw) during balloon occlusion were measured, both in a resting state and during infusion of intravenous adenosine, allowing the calculation of the pressure-derived collateral pressure index at rest and hyperaemia (CPIrest and the collateral fractional flow reserve [FFRcoll], respectively). Measurements were repeated 3 months later during angiographic follow-up. RESULTS: Eighty-one patients had physiological measurements at baseline and follow-up. In the final cohort the mean age was 64 years and 82% were male. The mean maximal stent diameter and total stent length were 3.2±0.5 mm and 68±31 mm, respectively. Successful strategies were antegrade wiring (64.2%), antegrade dissection re-entry (8.6%), and retrograde dissection re-entry (27.1%). Between the index procedure and follow-up, wedge pressure decreased from 34±11 mmHg to 21±8.5 mmHg (p<0.01), respectively. FFRcoll changed from 0.34±0.11 to 0.19±0.09 (p<0.01) at follow-up and CPIrest from 0.40±0.14 to 0.17±0.09 (p<0.01). Absolute maximum collateral flow decreased from 55±32 ml/min directly after PCI to 38±24 ml/min (p<0.01). There was no relation between the recanalisation technique and changes in FFRcoll. CONCLUSIONS: There was a significant reduction in collateral flow over time, independent of the recanalisation technique.

Extremity Dysfunction After Large-Bore Radial and Femoral Arterial Access.

Background The use of large-bore (LB) arterial access and guiding catheters has been advocated for complex percutaneous coronary intervention. However, the impact of LB transradial access (TRA) and transfemoral access (TFA) on extremity dysfunction is currently unknown. Methods and Results The predefined substudy of the COLOR (Complex Large-Bore Radial PCI) trial aimed to assess upper and lower-extremity dysfunction after LB radial and femoral access. Upper-extremity function was assessed in LB TRA-treated patients by the Quick Disabilities of the Arm, Shoulder, and Hand questionnaire and lower-extremity function in LB TFA-treated patients by the Lower Extremity Functional Scale questionnaire. Extremity pain and effect of access site complications and risk factors on extremity dysfunction was also analyzed. There were 343 patients who completed analyzable questionnaires. Overall, upper and lower-extremity function did not decrease over time when LB TRA and TFA were used for complex percutaneous coronary intervention, as represented by the median Quick Disabilities of the Arm, Shoulder, and Hand score (6.8 at baseline and 2.1 at follow-up, higher is worse) and Lower Extremity Functional Scale score (56 at baseline and 58 at follow-up, lower is worse). Clinically relevant extremity dysfunction occurred in 6% after TRA and 9% after TFA. A trend for more pronounced upper-limb dysfunction was present in female patients after LB TRA (P=0.05). Lower-extremity pain at discharge was significantly higher in patients with femoral access site complications (P=0.02). Conclusions Following LB TRA and TFA, self-reported upper and lower-limb function did not decrease over time in the majority of patients. Clinically relevant limb dysfunction occurs in a small minority of patients regardless of radial or femoral access. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03846752.

ULTrasound-guided TRAnsfemoral puncture in COmplex Large bORe PCI: study protocol of the UltraCOLOR trial.

INTRODUCTION: Although recently published evidence favours transradial access (TRA) when using large-bore guiding catheters for percutaneous coronary intervention (PCI) of complex coronary lesions, the femoral artery will still be used in a considerate proportion of patients undergoing complex PCI, especially in PCI of chronic total occlusions (CTO). Ultrasound-guided puncture of the femoral artery may reduce clinically relevant access site complications, but robust evidence is lacking up to date. METHODS AND ANALYSIS: A total of 542 patients undergoing complex PCI, defined as PCI of CTO, complex bifurcation, heavy calcified lesion or left main, in which the 7-F or 8-F transfemoral access is required, will be randomised to ultrasound-guided puncture or fluoroscopy-guided puncture. The primary outcome is the incidence of the composite end-point of clinically relevant access site related bleeding and/or vascular complications requiring intervention. Access site complications and major adverse cardiovascular events up to 1 month will also be compared between both groups. ETHICS AND DISSEMINATION: Ethical approval for the study was granted by the local Ethics Committee ('Medisch Ethische Toetsing Commissie Isala Zwolle') for all Dutch sites, 'Comité Medische Ethiek Ziekenhuis Oost-Limburg' for Hospital Oost-Limburg, 'Comité d'éthique CHU-Charleroi-ISPPC' for Centre Hospilatier Universitaire de Charleroi and 'Ethik Kommission de Ärztekammer Nordrhein' for Elisabeth-Krankenhaus). The trial outcomes will be published in peer-reviewed journals of the concerned literature. The ultrasound guided transfemoral access in complex large bore PCI trial has been administered in the ClinicalTrials.gov database, reference number: NCT03846752. REGISTRATION DETAILS: ClinicalTrials.gov identifier: NCT03846752.