Clinical Research Directory

Post-Induction Low Cardiac Output Syndrome in Coronary Artery Bypass Graft Surgery

Hemodynamic change after induction of general anesthesia is usually judged from mean arterial pressure. Pressure, however, is a surrogate for flow, and the two can separate: cardiac output may fall while arterial pressure remains apparently adequate. The interval that follows induction of anesthesia, before surgical stimulation begins and while hemodynamic conditions are determined by anesthetic management alone, has not been characterized in terms of flow. This study is designed to define post-induction low cardiac output (PiLCOs) in patients undergoing coronary artery bypass grafting. This is a prospective, observational, two-centre cohort study. Consecutive adults undergoing isolated coronary artery bypass grafting with cardiopulmonary bypass at two tertiary cardiovascular surgery centre will be enrolled. No aspect of anesthetic or surgical management will be altered for the purposes of the study. An arterial catheter is sited before induction while the patient is awake, and cardiac index is recorded continuously at 30-second intervals by arterial waveform analysis. Mean arterial pressure, heart rate, stroke volume index and cardiac index are recorded at the same resolution. The analysis window is the 30 minutes that follow induction of anesthesia. The period of cardiopulmonary bypass is excluded from all analyses, because flow during bypass is generated by the pump rather than by the heart. The primary outcome has two components, both defined over that window and both referenced to a cardiac index threshold of 2.0 L/min/m2. The first is the total time spent below threshold, in minutes. The second is the cumulative low-output burden, defined as the integral over time of the difference between the threshold and the measured cardiac index, taken only where that difference is positive. Dimensional analysis reduces the unit of burden to L/m2, a body-surface-indexed volume of undelivered flow, which multiplied by body surface area yields an absolute flow deficit in liters. Time below threshold describes how long the exposure lasts and cumulative burden describes how deep it is. The two together define the exposure, and neither alone is sufficient. Secondary outcomes are the same two measures computed at cardiac index thresholds of 2.2 and 2.5 L/min/m2; the incidence of PiLCOs, defined as at least one measurement below 2.0 L/min/m2 within the window; the time-weighted average depth across the window and the median depth sustained while below threshold; the distribution of cumulative burden across the three consecutive ten-minute segments of the window; and the time from induction to the first measurement below threshold. Exploratory analyses will examine the association between the presence and the magnitude of PiLCOs and the postoperative course, including acute kidney injury, serum lactate, duration of mechanical ventilation, intensive care unit and hospital length of stay, and mortality. All outcome analyses are treated as exploratory and hypothesis-generating, and no adjustment is made for multiple comparisons. Sample size was derived from an internal pilot of 30 patients, comprising the first 15 consecutive patients enrolled at each centre. In that pilot the standard deviation of time below threshold was 8.14 min and the incidence of PiLCOs was 70.0%. Setting the half-width of the 95% confidence interval at 1.7 min for mean time below threshold requires 88 patients, and setting it at 9.5 percentage points for incidence requires 90; the larger figure was carried forward and rounded to 90, allocated as 45 patients per centre. Allowing 15% for withdrawal, protocol deviation and unusable recordings gives a planned enrollment of 104 patients. Because the study estimates the frequency and the magnitude of an event that has not previously been characterized, rather than testing a prespecified superiority hypothesis, sample size is based on the precision of estimation rather than on power.

ShockFast Intravascular Lithotripsy Device for Treatment of Calcified Coronary Lesions

Coronary artery disease is caused by narrowing of the artery lumen. Treatment with Percutaneous Coronary Intervention (PCI) may be needed. This is a minimally invasive procedure used to treat narrowed or blocked coronary arteries. Sometimes a stent is placed to keep the artery open. If the lesions in the coronary artery are calcified, this may cause difficulties for successful stent placement. The calcified plaques can be fractured via intravascular lithotripsy (IVL) with devices like ShockWave IVL and ShockFast IVL. The aim of this study is to compare the this relatively new ShockFast IVl with the more widely used ShockWave IVL.

ESPB vs SPSIP for Postoperative Analgesia After CABG

This prospective, randomized, active-controlled, double-blind, parallel-group study compares the postoperative analgesic efficacy and safety of ultrasound-guided bilateral Erector Spinae Plane Block (ESPB) versus bilateral Serratus Posterior Superior Intercostal Plane Block (SPSIPB) in adult patients (45-85 years, ASA I-III) undergoing elective coronary artery bypass graft surgery. The primary outcome is postoperative pain intensity assessed by Numeric Rating Scale (NRS) at 2, 4, 8, 16, 24, and 48 hours after surgery. Secondary outcomes include intraoperative fentanyl/remifentanil consumption, postoperative morphine consumption, patient-controlled analgesia (PCA) demand/delivery parameters (if PCA is used), need for rescue analgesics, extubation and mobilization times, peak inspiratory flow measured by incentive spirometry at predefined time points, ICU and hospital length of stay, recovery quality (QoR-15 at 0, 24, and 48 hours), mortality, and block-related adverse events.

Effect of Dapagliflozin on Right Ventricular-Pulmonary Artery Coupling After Off-Pump Coronary Atery Bypass Grafting

This prospective, single-center observational study evaluates the effect of dapagliflozin 10 mg/day on right ventricular-pulmonary artery coupling measured by the TAPSE/PASP ratio in 72 patients with left ventricular ejection fraction \<50% after off-pump coronary artery bypass grafting (OPCAB). The primary outcome is the change in TAPSE/PASP ratio from 1 month after surgery (before dapagliflozin) to 7 months after surgery (after 6 months of dapagliflozin therapy).

Ultralow Dose PET Imaging of 18F-flurpiridaz

The goal of this clinical trial is to evaluate an investigational ultralow dose positron emission tomography (PET) imaging technique for known or suspected coronary artery disease (for detecting myocardial ischemia or infarction) detection and monitoring. The main question it aims to answer is: Can the investigators optimize the timing, scan duration, and image reconstruction to reduce the radiation dose 10-100 fold of the current clinical standard? Participants will be injected with a radioactive tracer called Fluorine-18 (18F)-flurpiridaz and be imaged on a new type of high sensitivity PET scanner for up to 3 hours

Optical Coherence Tomography: Prognostic Value and Artificial Intelligence

This study aims to evaluate the prognostic value of optical coherence tomography (OCT) imaging of the coronary arteries. OCT provides high-resolution images of the vessel wall and stented segments during routine cardiac catheterization. All patients who undergo OCT as part of their clinical care are invited to participate in this prospective registry. The study will examine whether specific OCT-derived characteristics-such as plaque morphology, vulnerable features, or indicators of stent optimization-are associated with long-term clinical outcomes. Follow-up information on symptoms, medication use, hospitalizations, cardiac procedures, and major cardiac events will be collected through medical records, questionnaires, and national registry data over a period of up to 10 years. In addition, pseudonymized OCT pullbacks will be used to support the development of an artificial intelligence (AI) algorithm for automated annotation of OCT images. This algorithm may help improve the clinical interpretation of OCT by identifying relevant imaging features in a consistent and efficient manner. Participation is voluntary and includes permission to use clinical data, OCT images, and follow-up information for research purposes. Data are coded to protect participant privacy and stored securely according to applicable regulations. The results of this study may contribute to better understanding of coronary plaque characteristics and may support improved decision-making in interventional cardiology.

Safety and Effectiveness of the Single-Use Coronary Forward Intravascular Lithotripsy Catheter Combined With the Intravascular Lithotripsy Therapy Device

The FORWARD IVL trial is a Prospective, Multicenter Study conducted to assess the safety and effectiveness of the Single-Use Coronary Forward Intravascular Lithotripsy Catheter combined with the Intravascular Lithotripsy Therapy Device for the pre-treatment of calcified, stenotic de novo coronary artery lesions .