Kazuki Matsuhashi

Background: Compared with isolated aortic valve replacement (AVR), echocardiographic hemodynamics after Wheat and Bentall procedures, both involving replacement of the proximal ascending aorta with a smaller-diameter graft, have been less thoroughly investigated. Methods: We analyzed 213 patients who received 21 mm or 23 mm aortic bioprostheses (AVR, n = 138; Wheat, n = 43; Bentall, n = 32). Transthoracic echocardiography was performed before and after surgery, and the proximal ascending aortic area (Aa) was assessed using contrast-enhanced computed tomography. Results: The maximal pressure gradient (PG max), derived from the simplified Bernoulli equation, was significantly lower in the Bentall group, whereas pressure recovery (PR), calculated using Voelker's equation, was lower in the AVR group. A smaller Aa was associated with a higher PG max in the AVR group. The Bentall group exhibited significantly lower energy loss (EL). In propensity score-matched analyses to minimize potential confounding factors, the AVR group showed a significantly lower PR and higher EL than the Wheat group; a significantly higher PG max, lower PR, and higher EL than the Bentall group; and a significantly similar PR but lower EL in the Bentall group compared with the Wheat group. Conclusions: Although limited to bioprosthetic valves, caution is warranted when interpreting echocardiographic PG max after AVR in patients with a small ascending aorta. However, overestimation of PG max was not observed in either the Wheat or Bentall groups, even though both demonstrated higher PR and lower EL compared with the AVR group.

OBJECTIVE: To investigate the impact of the discrepancy between the predicted annuloplasty ring size determined by preoperative transesophageal echocardiography and the actual ring size on the outcomes of mitral valve repair (MVr) using primarily the loop technique. METHODS: Among 370 patients who underwent MVr between January 2008 and December 2024, 154 who underwent MVr with the semirigid ring for degenerative disease were involved in this study. Ring size was estimated according to the lengths of A2 and P2 by transesophageal echocardiography. Patients were classified into 3 groups-small, match, and large-based on the discrepancy between the predicted and actual ring sizes. RESULTS: Compared with the other small and match groups, patients in the large group had shorter anterior leaflet length (P = .03), smaller posterior leaflet angle (P = .01) and smaller coaptation depth (P = .03) in the coaptation triangle. There was no significant difference in coaptation length among the 3 groups. The cumulative incidence of mitral regurgitation (MR) grade ≥2 was 0.6% at 1 year, 5% at 5 years, and 24% at 10 years, whereas that of a mean transmitral pressure gradient ≥5 mm Hg were 5%, 13%, and 16%, respectively. Fine-Grey multivariable analysis identified larger posterior leaflet angle after repair as a risk factor for recurrence of MR grade ≥2 and larger body surface area, smaller prosthesis size, and shorter coaptation length as risk factors for functional mitral stenosis. CONCLUSIONS: Size mismatch of the prosthesis ring did not change the coaptation length, late MR recurrence, or functional mitral stenosis after MVr.

Fractional flow reserve (FFR) has been well validated as a modality for evaluating myocardial ischemia, demonstrating the superiority of FFR-guided percutaneous coronary intervention (PCI) over conventional angiography-guided PCI. As a result, the strategy for coronary artery bypass grafting (CABG) is shifting toward FFR guidance. However, the advantage of FFR-guided CABG over angiography-guided CABG remains unclear. While FFR-guided CABG can help avoid unnecessary grafting in cases of moderate stenosis, it may also carry the risk of incomplete revascularization. The limited use of FFR due to the need for hyperemia has led to the development of non-hyperemic pressure ratios (NHPRs). NHPR pullback provides trans-stenotic pressure gradients, which may offer valuable insights for CABG strategies. Recently, computed tomographic coronary angiography (CTCA) has emerged as a non-invasive modality that provides accurate data on lesion length, diameter, minimum lumen area, percentage stenosis, and the volume and distribution of high-risk plaques. With the introduction of FFR-CT, CTCA is now highly anticipated to provide both functional evaluation (of myocardial ischemia) via FFR-CT and anatomical information through serial quantitative assessment. Beyond the diagnostic phase, CTCA, augmented by automatic artificial intelligence, holds great potential for guiding therapeutic interventions in the future.

As the current guidelines on myocardial revascularization recommend, transit-time flow measurement (TTFM) is increasingly used for intraoperative graft flow analysis during coronary artery bypass grafting (CABG) as a less invasive, more highly reproducible, and less time-consuming method. In addition to the morphological assessment using color Doppler, mean graft flow (Qm) > 15 ml/min, pulsatility index (PI) < 5.0, diastolic filling (DF) > 50%, and systolic reverse flow (SRF) < 4% have been reported to predict patent CABG grafts. However, it is difficult to determine the clear-cut cut-off value of these parameters, because they varies with the hemodynamic characters, including fractional flow reserve (FFR) of the target coronary artery. In addition to these parameters, we focused on fast Fourier transform (FFT) analysis, because the TTFM waveform morphology may be more important than Qm itself. FFT analysis is based on the principle that any periodic waveforms can be broken down into a series of pure sine waves or harmonics. Herein we review FFT analysis of the intraoperative TTFM waveforms for quality assessment of CABG grafts.

Background: We have employed a conservative management approach, including intensive control of both blood pressure and heart rate, in patients with aortic intramural hematoma (AIMH) and retrograde thrombosed type A acute aortic dissection (RT-TAAAD), sharing common clinical and imaging characteristics. Methods: To evaluate the outcomes of our conservative management approach, we retrospectively reviewed the clinical records of 98 patients diagnosed with AIMH or RT-TAAAD from January 2008 to March 2023. A conservative management approach was applied, except for those patients with an aortic diameter ≥ 55 mm, false lumen expansion, or cardiac tamponade, who underwent emergency aortic repair. Results: Besides 2 patients, who declined surgery and subsequently died from aortic rupture, 18 patients underwent urgent aortic surgery, while 78 did not. Multivariable logistic regression analysis identified the extrusion type of ulcer-like projections (ULPs) on admission and a maximum aortic diameter ≥ 45 mm on Day 1 as risk factors for acute aortic surgery. Among the 78 patients who were discharged, 9 (12%) underwent aortic surgery, while 69 (88%) did not, with a median follow-up of 44 months. The overall actuarial aortic surgery-free rates were 78% at 1 year and 72% at 5 years, respectively. A Cox proportional hazards analysis identified ULPs and an aortic diameter ≥ 45 mm at discharge as risk factors for late aortic surgery. Conclusions: The early and late outcomes of our conservative strategy for AIMH and RT-TAAAD demonstrate favorable surgery-free rates. The extrusion type of ULPs on admission and an aortic diameter ≥ 45 mm on Day 1 are predictors of acute aortic surgery, while ULPs and an aortic diameter ≥ 45 mm at discharge are predictors of late surgery.