The effect of hydrostatic pressure on invasive coronary pressure measurements: Comparison with [O]HO-positron emission tomography flow data.

Background: Fractional flow reserve (FFR) has emerged as the invasive gold standard for assessing vessel-specific ischemia. However, FFR measurements are influenced by the hydrostatic effect, which might adversely impact the assessment of ischemia.

Aims: This study aimed to investigate the impact of hydrostatic pressure on FFR measurements by correcting for the height and comparing FFR with [O]HO positron emission tomography (PET)-derived relative flow reserve (RFR).

Myocardial Infarction and Coronary Anomalies in a 25-Year-Old Neurofibromatosis Type 1 Patient.

A 25-year-old male with neurofibromatosis type 1 presented with acute ST-segment elevation myocardial infarction. Coronary imaging revealed an aberrant right coronary anatomy, ectatic coronary arteries, and significant stenosis. Based on previous literature and clinical presentation, this case highlights the potential role of neurofibromatosis in the pathogenesis of coronary artery disease.

Upper extremity versus lower extremity for secondary access during transcatheter aortic valve implantation: rationale and design of the randomised TAVI XS trial.

Background: During transcatheter aortic valve implantation (TAVI), secondary access is required for angiographic guidance and temporary pacing. The most commonly used secondary access sites are the femoral artery (angiographic guidance) and the femoral vein (temporary pacing). An upper extremity approach using the radial artery and an upper arm vein instead of the lower extremity approach using the femoral artery and femoral vein may reduce clinically relevant secondary access site-related bleeding complications, but robust evidence is lacking.

Fluid-filled versus sensor-tipped pressure guidewires for FFR and P/P 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 P/P measurement with a fluid-filled and a sensor-tipped pressure guidewire simultaneously.

Using Upper Arm Vein as Temporary Pacemaker Access Site: A Next Step in Minimizing the Invasiveness of Transcatheter Aortic Valve Replacement.

The femoral vein is commonly used as a pacemaker access site during transcatheter aortic valve replacement (TAVR). Using an upper arm vein as an alternative access site potentially causes fewer bleeding complications and shorter time to mobilization. We aimed to assess the safety and efficacy of an upper arm vein as a temporary pacemaker access site during TAVR.

Rationale and design of the pullback pressure gradient (PPG) global registry.

Introduction: Diffuse disease has been identified as one of the main reasons leading to low post-PCI fractional flow reserve (FFR) and residual angina after PCI. Coronary pressure pullbacks allow for the evaluation of hemodynamic coronary artery disease (CAD) patterns. The pullback pressure gradient (PPG) is a novel metric that quantifies the distribution and magnitude of pressure losses along the coronary artery in a focal-to-diffuse continuum.

Potential effects of the hydrostatic pressure gradient on hyperemic and nonhyperemic pressure ratios.

When measuring hyperemic and nonhyperemic pressure ratios with traditional sensor-tipped wires, the inevitable hydrostatic pressure gradient (HPG) may influence treatment decisions. This study aimed to simulate and analyze the effect of a hydrostatic pressure gradient on different indices of functional lesion severity. A hypothetical P-P height difference and subsequent hydrostatic pressure gradient based on previous literature was applied to the pressure measurements from the CONTRAST study.

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.

Accuracy and Potential Benefit of Ultraselective Invasive Coronary Angiography Guided by Computed Tomographic Coronary Angiography.

Objectives: It is unknown whether computed tomographic coronary angiography (CTCA) can be used to perform ultraselective invasive coronary angiography (ICA) by only visualizing the abnormal coronary artery on CTCA and defer visualization of the normal contralateral coronary artery. This study assessed the accuracy of CTCA in patients with coronary artery disease (CAD) on CTCA limited to either the left (LCA) or right coronary artery (RCA) in predicting a contralateral coronary artery without abnormalities on CTCA determined to be normal by ICA.

Methods: This retrospective analysis included patients with CAD limited to the LCA or RCA on CTCA.

The Allegra transcatheter heart valve: Short term results from a multicenter registry.

Objectives: We aimed to determine the safety and efficacy of the Allegra transcatheter heart valve (THV) for the treatment of severe aortic valve stenosis in a large patient population treated under real-world conditions.

Background: The Allegra is a novel self-expanding THV with supra-annular bovine leaflets. The valve is available in three different sizes (23, 27, and 31 mm), all are delivered through an 18F sheath.

Intra-aortic balloon pump counterpulsation in extensive myocardial infarction with persistent ischemia: The SEMPER FI pilot study.

Objectives: This study aimed to prospectively investigate intra-aortic balloon pump counterpulsation (IABP) support in large myocardial infarction complicated by persistent ischemia after primary percutaneous coronary intervention (PCI).

Background: Use of IABP is suggested to be effective by increasing diastolic aortic pressure, thereby improving coronary blood flow. This can only be expected with exhausted coronary autoregulation, typical in acute myocardial infarction complicated by persistent ischemia.

Comparison of Different Diastolic Resting Indexes to iFR: Are They All Equal?

Background: Pressure measurement for the duration of the wave-free period (WFP) is considered essential for resting-state physiological assessment of coronary stenosis severity using the instantaneous wave-free ratio (iFR).

Objectives: The aim of this study was to compare other diastolic resting indexes to iFR.

Methods: In the population of the VERIFY2 (Pd/Pa vs iFR in an Unselected Population Referred for Invasive Angiography) study, iFR calculated by proprietary software (Volcano Harvest, Volcano Corporation, Rancho Cordova, California) was compared with the ratio of resting distal coronary pressure and aortic pressure during the complete duration of diastole (dPR), 25% to 75% of diastole (dPR), and midpoint of diastole (dPR), along with Matlab calculated iFR (iFR) and iFR-like indexes shortening the length of the WFP by 50 and 100 ms (iFR and iFR), respectively.

Safety and feasibility of selective intracoronary hypothermia in acute myocardial infarction.

Aims: Hypothermia reduces reperfusion injury and infarct size in animal models of acute myocardial infarction if started before reperfusion. Human studies have not confirmed benefit, probably due to insufficient myocardial cooling and adverse systemic effects. This study sought to assess the safety and feasibility of a novel method for selective, sensor-monitored intracoronary hypothermia.

Intracoronary Hypothermia Before Reperfusion to Reduce Reperfusion Injury in Acute Myocardial Infarction: A Novel Hypothesis and Technique.

Because current reperfusion strategies in acute myocardial infarction (AMI) seem to be exhausted in terms of additional mortality benefit, there remains a need for new methods to attenuate reperfusion injury and, thereby, further reduce myocardial infarct size and improve long-term survival. Therapeutic hypothermia (32-35°C) diminishes reperfusion injury and reduces infarct size in a variety of animal models of AMI if provided before reperfusion. In human studies this reduction has not been confirmed so far, most likely because systemic cooling acts slowly, and therefore, the target temperature is not reached in time or at all in a substantial number of patients.

Intracoronary hypothermia for acute myocardial infarction in the isolated beating pig heart.

Hypothermia may attenuate reperfusion injury and thereby improve acute myocardial infarction therapy. Systemic cooling trials failed to reduce infarct size, perhaps because the target temperature was not reached fast enough. The use of selective intracoronary hypothermia combined with intracoronary temperature monitoring allows for titrating to target temperature and optimizing the cooling rate.