Volume 101 ·  Issue 39 ·  2021

In recent years, cardiovascular imaging has become an important tool to evaluate cardiovascular diseases, which can provide anatomical and function information in multidimensional ways, and is expected to have a positive impact on the diagnosis and treatment of cardiovascular diseases. This editorial briefly describes the current status of advanced cardiovascular CT imaging in cardiovascular diseases on diagnosis, treatment, decision-making and prognostic evaluation, including CT-derived flow fractional reserve, CT perfusion, pericoronary adipose tissue and application of artificial intelligence, in order to promote the clinical transformation of these technologies.

Atherosclerotic cardiovascular disease (ASCVD) remains the leading cause of human deaths all over the world. Dyslipidemia is the central mechanism of the prevalence and development of ASCVD, which has been regarded as a remediable risk factor for cardiovascular disease. It′s well known that the traditional lipid parameter, low-density lipoprotein cholesterol (LDL-C), is the primary target for lipid interfering in ASCVD. However, both randomized controlled trials and real-world studies have suggested that residual risk persists in spite of the well-controlled LDL-C levels according to current guidelines. Hence, in recent years, a series of studies have indicated that many novel lipid indicators are closely correlated with the residual risk of ASCVD. This article aimed to summarize the research status of these non-traditional lipid parameters in cardiovascular field.

To determinate the range of quantitative myocardial perfusion parameters (MBF, MBV) in subjects without coronary artery lesions by dynamic computed tomography myocardial perfusion imaging (CTP).

Subjects with occasional chest tightness or family history of coronary artery disease coming to Fuwai Hospital underwent coronary computed tomography angiography (CCTA) were prospectively enrolled. A total of 34 subjects [mean age (50±7) years, range from 33 to 65 years; 15 male and 19 female] were enrolled. Coronary lesions were not confirmed in any subjects using CCTA and volunteered for stress and rest dynamic CTP examination. MBF and MBV values were calculated in each myocardial segment using a 17-segment model. The global ranges of MBF and MBV were analyzed, and the gender variability and regional variability were compared.

The mean global MBF and MBV at rest and under stress were (115.5±27.4) ml·100 g^-1·min^-1, (212.8±40.8) ml·100 g^-1·min^-1 and (17.6±4.0) ml/100 g, (25.8±4.6) ml/100 g, respectively. The absolute and resolute reserves of MBF and MBV [(102.8±41.5) ml·100 g^-1·min^-1, 107.7%±52.5%; (9.3±5.2) ml/100 g, 62.1%±47.4%] were highest in the right coronary artery territory, but without any significant differences. The stress MBF and absolute reserve of MBF in females were higher than those of males [(228.6±39.9) ml·100 g^-1·min^-1, (113.3±46.2) ml·100 g^-1·min^-1; (192.8±33.4) ml·100 g^-1·min^-1, (77.0±41.2) ml·100 g^-1·min^-1] (both P<0.05). The MBF resolute reserve, rest MBV, stress MBV and MBV absolute and resolute reserves were higher in females, but without significant differences (all P>0.05).

The mean global MBF and MBV at rest and under stress were (115.5±27.4) ml·100 g^-1·min^-1, (212.8±40.8) ml·100 g^-1·min^-1 and (17.6±4.0) ml/100 g, (25.8±4.6) ml/100 g. The MBF under stress perfusion and MBF absolute reserve of females are higher than those of males.

To investigate the image quality of coronary CT angiography (CCTA) subjected to deep learning-based reconstruction algorithm (DLR) method and its diagnostic performance for stenosis caused by coronary calcified lesions.

We enrolled 33 consecutive patients with known or suspected coronary artery disease (CAD) who underwent CCTA and subsequently invasive coronary angiography (ICA) within 1 month in the department of radiology, Peking Union Medical College Hospital between February 2020 and February 2021. Among them, there are 26 males and 7 females, age range from 45 to 86 (61.9±9.0) years. The CCTA images were reconstructed with DLR and hybrid iterative reconstruction (HIR). Image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were calculated on the aorta root, left main artery, proximal left anterior descending, left circumflex, and right coronary artery of the CCTA images and were used to evaluate the objective image quality (IQ). Subjective IQ score was graded using Likert four-point scale (1 for excellent and 4 for poor). The diagnostic performance of obstructive coronary artery disease caused by calcified lesions on CCTA subjected to DLR and HIR methods were evaluated using ICA as the reference standard.

A total of 123 lesions in 33 patients were included in the analysis. Image noise of DLR image was significantly lower than that on HIR image(defined as the standard deviation of the attenuation values in the aortic root: 18.12±3.66 vs 24.19±5.71, P<0.001), CNR and SNR of DLR image in the aortic root were higher (CNR:43.83±23.73 vs 26.38±9.69,P<0.001,SNR:26.66±7.83 vs 21.23±8.65,P<0.001). Subjective scores of DLR was better than HIR image (1.12±0.41 vs 1.46±0.60,P<0.001). The sensitivity, specificity and accuracy of DLR and HIR images for diagnosing obstructive coronary artery disease caused by calcified lesions were 100.0%, 77.4%, 78.9% and 100.0%, 63.5%, 65.9%%, respectively. The number of false positive cases on DLR image decreased by 38% compared with HIR.

Artificial intelligence based DLR can significantly reduce the image noise and improve the image quality of CCTA. DLR helps to improve the diagnostic performance of CCTA in assessing obstructive coronary artery disease caused by calcified lesions, which may have good clinical application value.

To explore the influence of measurement sites on the diagnostic performance of coronary computed tomography angiography (CCTA) -derived instantaneous wave-free ratio (iFR_CT) for coronary stenosis ischemia.

A total of 44 patients, including 27 males and 17 females aged from 44 to 83 (59±90) years, who underwent coronary computed tomography angiography (CCTA) and invasive fractional flow reserve (FFR) in the Department of Radiology, Eastern Theater Command General Hospital from February 2009 to May 2018 were retrospectively collected. Based on CCTA images, iFR_CT values at different locations (stenosis, proximal downstream of stenosis, 2 cm downstream of stenosis, 3 cm downstream of stenosis, and 4 cm downstream of stenosis) were calculated through fluid mechanics simulation. With invasive FFR≤0.80 as the reference standard, receiver operating characteristic (ROC) was used to analyze and evaluate the diagnostic performance of iFR_CT in different sites. Bland-Altman and spearman correlation coefficient were used to analyze the consistency between iFR_CT and invasive FFR. Intraclass correlation coefficient (ICC) and spearman correlation coefficient were used to test the repeatability of iFR_CT.

iFR_CT values at the proximal downstream of the stenosis (approximately 1 cm downstream of the stenosis) was superior to other measurement sites in the diagnosis of coronary ischemic specific stenosis. The threshold, area under the curve, sensitivity, specificity and accuracy of iFR_CT at the stenosis were 0.91, 0.87 (95%CI:0.76~0.96), 82% (95%CI:48%~97%), 76% (95%CI:57%~88%) and 77% (95%CI: 63%~87%), respectively. Bland-Altman analysis showed that the mean differences between iFR_CT and FFR at the proximal downstream of the stenosis was 0.07 (95%LoA: 0.06~0.09) and Spearman correlation coefficient was 0.53 (P<0.001). At the proximal downstream of the stenosis, the intraobserver ICC of iFR_CT was 0.92 (95%CI: 0.85 ~0.95), the correlation coefficient was 0.85 (P<0.001); the interobserver ICC was 0.84 (95%CI: 0.60~0.94), correlation coefficient was 0.75 (P<0.001), demonstrating good repeatability between iFR_CT and FFR.

With the invasive FFR value as reference standard, iFR_CT had a high diagnostic performance in detecting myocardial ischemia and the best measurement site was the proximal downstream of the stenosis.

To explore the association of coronary perivascular fat attenuation index (FAI), the parameters of plaque and fractional flow reserve (FFR).

A total of 113 patients (with 141 plaques) (78 males and 35 females, age from 40 to 83 years) with stable coronary artery disease were retrospectively collected from Jingling Hospital and Shanghai Sixth People′s Hospital. All the patients underwent coronary CT angiography and invasive FFR examinations. The quantitative and qualitative parameters of plaque and vessel (such as the length and volume of plaque, the characteristics of plaque and high-risk plaque) and the FAI around the plaque were measured. The patients were divided into positive FAI group (n=46) and negative FAI group (n=66) according to the standard of whether the threshold of FAI≥ -70 HU. The quantitative indexes, including age, the length and volume of plaque, minimal lumen area (MLA) and FAI, as well as the qualitative indexed, including the characteristics of plaque, the number and characteristic of high-risk plaque and the number of patients and plaque with positive FFR were compared between the two groups. Further, logistic regression analysis was performed to analyze the correlation among myocardial ischemia, age, the length of plaque, minimal lumen area (MLA), FAI and so on. ROC curve was used for evaluating the performance of each parameter.

Compared to the negative FAI group, positive FAI group had lower MLA (2.00±1.33 mm² vs 4.13±2.41 mm², P<0.001). The proportion of patients and vessels with FFR<0.75 in positive FAI group were significantly higher than that in negative FAI group (21.3% vs 4.5%,P=0.006; 23.2% vs 8.2%, P=0.016). The FAI between high-risk plaque and non-high-risk plaque had no significant difference (21.2% vs 16.1%, P=0.451). FAI predicted myocardial ischemia (AUC=0.666, P=0.021) and significantly improved the prediction efficiency of complex model(0.915 vs 0.951,P=0.033).

Lower MLA and higher incidence of myocardial ischemia were associated with patients with higher FAI. In addition, FAI has a certain prediction efficiency and can provide incremental value for the determination of myocardial ischemia.

To explore the effect of modified electroconvulsive therapy (MECT) on resting-state functional connectivity (RSFC) in patients with major depressive disorder (MDD).

Patients with MDD from Anhui Mental Health Center from October 2017 to May 2019 were included. Using bilateral nucleus accumbens (NAcc) as seed points, changes of RSFC were investigated before and after MECT through resting-state functional magnetic imaging (fMRI). Antidepressant effects were measured by 17 items of Hamilton Depressive Rating Scale (HDRS-17). Correlation analysis was performed between changed HRSD-17 scores and changes of functional connectivity.

A total of 40 MDD patients (10 males and 30 females), aged (38±11) years, who received MECT were included in the study. After MECT, patients showed increased RSFC in the right NAcc (rNAcc) and superior frontal gyrus (P<0.001), right supramarginal gyrus (P<0.001), right angular gyrus (rAG) (P= 0.017), right inferior parietal lobule (P= 0.017), left superior frontal gyrus (LSFG) (P<0.001), left middle temporal gyrus (P=0.017) and left angular gyrus (LAG) (P=0.012), respectively. The RSFC changes of rNAcc-LSFG (r=-0.454, P = 0.003), rNAcc-rAG (r=-0.437, P=0.005) and rNAcc-lAG (r=-0.383, P=0.015) were negatively correlated with the changes of HRSD-17 scores.

MECT may alleviate major depression by regulating the functional connectivity between the rNAcc and bilateral angular gyrus and left superior frontal gyrus.

To investigate the characteristics of glutamatergic neurotransmitter and neurotransmission dysfunction in patients with major depressive disorder (MDD) and its relationship with clinical characteristics.

Fifty-two patients with MDD and 51 healthy controls were selected. Hamilton Depression scale-17 (HAMD-17) and Hamilton Anxiety Scale (HAMA) were used to evaluate the symptoms of depression and anxiety. The serum glutamate level was measured by enzyme-linked immunosorbent assay (ELISA). Reverse transcription polymerase chain reaction (RT-PCR) was used to detect the mRNA level of NR1 subunit of NMDA receptor.

There was no significant difference in gender and age between MDD group and healthy control group. Compared with the control group, the level of serum glutamate [(35±6) mg/L vs (29±6) mg/L, P = 0.021] and mRNA level of NR1 (1.5±0.8 vs 0.8±0.6, P = 0.001) in MDD group were significantly higher. In MDD group, serum glutamate level was positively correlated with depression core symptom score (r = 0.52, P = 0.028), and mRNA level of NR1 subunit was positively correlated with the total course of disease (r = 0.42, P = 0.024).

MDD patients may have disorder of glutamatergic neurotransmitter and abnormal expression of NR1 subunit.

To explore the efficacy of endovenous microwave ablation in treating primary varicose veins of the lower extremities.

A total of 214 patients with primary varicose veins of the lower extremities in the First Affiliated Hospital of Sun Yat-sen University from January 2017 to November 2019 were included and divided into microwave ablation group (n=128) and high ligation with microwave ablation group (n=86) according to surgical approach. Further subgroups including subgroup S (diameter<10 mm) and subgroup L (diameter≥10 mm) were established. The surgical success rate, postoperative incidence and recovery of local skin numbness and ecchymosis, and the postoperative recovery of active skin ulcer were compared between the two groups and subgroups.

The surgical success rate was 96% (136/141) in microwave ablation group, 100% in subgroup S (116/116), and 80% in subgroup L (20/25), respectively. In addition, the surgical success rate in high ligation with microwave ablation group, subgroup S, and subgroup L was all 100% (90/90, 73/73, and 17/17). In subgroup L of microwave ablation group, the diameter of 5 great saphenous veins in patients who failed the microwave ablation was 13.0-17.1 mm. The mean follow-up time was (24±4) months in microwave ablation group and (36±6) months in high ligation with microwave ablation group, respectively. In the microwave ablation group and high ligation with microwave ablation group, the incidence of postoperative skin numbness was 15.6% and 14.4%, respectively, and the incidence of skin ecchymosis was 5.7% and 3.3%, respectively, with no statistically significant difference between the two groups (both P>0.05). The rate of active skin ulcer in the two groups was 6.4% and 15.6%, respectively, and the difference was statistically significant (P=0.020). Local skin ecchymosis in the two groups recovered within 1 month after operation. Local skin numbness in both groups recovered within the maximum 2 years of follow-up, and active skin ulcer in both groups recovered within the maximum 1 years of follow-up.

The endovenous microwave ablation is safe and effective, especially combining with high ligation of great saphenous vein. Good follow-up results can be achieved for great saphenous vein with diameter smaller than 10 mm. However, for those with diameter greater than 10 mm, the surgical success rate of endovenous microwave ablation decreases.

To observe the efficacy and safety of S(+)-ketamine combined with sufentanil for patient-controlled intravenous analgesia (PCIA) in elderly patients undergoing laparoscopic radical resection of rectal cancer and explore its impact on patients′ early recovery.

One hundred and ten patients undergoing laparoscopic radical resection of rectal cancer in Affiliated Cancer Hospital of Zhengzhou University from December 2020 to March 2021, were divided into two groups (n=55) using a random number table: group S received PCIA, with continuous infusion of S(+)-ketamine combined with sufentanil, while group C received PCIA, with continuous infusion of sufentanil. PCIA was initiated at the end of the surgery, and the formulations were as follows: group S, S(+)-ketamine (1.44 mg/kg), sufentanil (1.05 μg/kg), ketorolac tromethamine (2.0 mg/kg) and tropisetron (5 mg), in 100 ml of normal saline; group C: sufentanil (1.50 μg/kg), ketorolac tromethamine (2.0 mg/kg) and tropisetron (5 mg), in 100 ml of normal saline. Postoperative visual analogue scale (VAS) and Ramsay sedation scale were recorded at 6, 12, 24, 36, 48 h after the surgery. The incidence of remedial analgesia, the effective compressions number of PCI during 48 h after the operation. Time to first ambulation, time to first anal exhaust, time to resume oral feeding were recorded. The occurrence of adverse effects was compared between the two groups.

A total of 10 patients were excluded during the study, including 4 cases of conversion to laparotomy, 3 cases of dropping out of the study, and 3 cases with operation time more than 4 hours. Finally, 50 cases in group S and 50 cases in group C completed the study. There were no significant differences in VAS scores and Ramsay sedation sores at all time points between two groups (all P>0.05). Likewise, there were also no significant differences in the number of remedial analgesia and effective compressions of PCIA during 48 h after the operation between the two groups (bothP>0.05). The total dosage of sufentanil consumption in group S [(64±9) μg] was lower than that in group C [(95±12) μg] within 48 h of PCIA, with a statistically significant difference (P<0.001). Time to first ambulation in group S was (1.1±0.2) d, which was shorter than that in group C [(1.6±0.5) d], and the difference was statistically significant (P<0.001). Likewise, time to first anal exhaust in group S [(1.3±0.4) d] was shorter than that in group C [(1.8±0.6) d], with a statistically significant difference (P<0.001). Additionally, time to resume oral feeding in group S was (2.5±0.6) d, which was shorter than that in group C [(3.1±0.7) d], and there was a statistically significant difference (P<0.001). The incidence of nausea, vomiting and pruritus in group S were 4.0%, 2.0% and 0, which were lower than that in group C (16.0%, 10% and 8.0%, respectively), with statistically significant differences (allP<0.05). No case with psychiatric symptoms was found in both groups.

When used for postoperative intravenous analgesia in elderly patients undergoing laparoscopic radical resection of rectal cancer, S(+)-ketamine combined with sufentanil can provide satisfactory analgesic effects, decrease total consumption of sufentanil and the incidence of adverse effects, and thus facilitate patientsʹ early recovery.

The clinical data of 47 patients [41 males, 6 females, aged (62±7) years] treated at the Department of Neurology of the Sixth Medical Center of PLA General Hospital from October 2018 to October 2020 who were diagnosed with severe bilateral vertebral artery stenosis/occlusion through Digital Subtraction Angiography (DSA) were retrospectively collected, and the characteristics of the compensatory pathways of collateral circulation were determined. Results showed that there were 8 intracranial and extracranial compensatory pathways, with posterior communicating artery as the major type (21 cases) for intracranial ones and deep carotid artery as the major type (16 cases) for extracranial ones. As the establishment of the compensatory pathway is closely related to the lesion site, DSA assessment for patients with severe bilateral vertebral artery stenosis/occlusion is helpful for clinicians to make judgement on prognosis of patients and choose individualized treatment plans.

To investigate the clinical effect of fibula transverse transport technique in the treatment of diabetic foot ulcer. Nine patients (7 males and 2 females) with diabetic foot ulcer were treated with fibula transverse transport technique from September 2017 to September 2020. The mean age was (55±9) years (ranged from 43 to 66 years). In terms of Wagner classification, 2 cases were in grade 2, 5 cases were in grade 3, and the other 2 cases were in grade 4. All of the cases involved ischemic ulcers or ischemic-nerve ulcers. The transcutaneous oxygen pressure (TcPO₂) of the dorsal foot of the affected limb was measured, with the ulcer healing and TcPO₂ changes recorded at follow-up. All the 9 patients were followed up for (23±12) months (3 to 38 months). It was found that all patients with foot ulcers were cured within (4.2±1.9) months (2 to 8 months), and all the patients obtained limb salvage. Besides, there was no serious complications occurred, such as skin necrosis and needle tract infection. Before the operation, the TcPO₂ of the affected foot was (28.6±3.8) mmHg(1 mmHg=0.133 kPa), while it was (35.0±5.6) mmHg three months after operation (P<0.05). The technique of fibula transverse transport can effectively improve the microcirculation function of diabetic foot, and it can promote the healing of the ulcer with few complications.

To evaluates the clinical outcome of the ankle arthroscopic resection of subfibula ossicles combined with modified Broström technique for pain on the external malleolus caused by subfibular ossicles in 15 patients from April 2014 to January 2019 treated in the Tianjin First Central Hospital. The patients included 6 males and 9 females, aged from 24 to 56 years, and the symptoms lasted for a mean of 7.8 months(1.0-27.0 months) before the operation. With a 12-month follow-up, the visual analog scale (VAS) pain score, American Orthopedic Foot and Ankle Society (AOFAS) score and Karlsson-Peterson (KP) score were used to assess the clinical outcome. The VAS pain score reduced from 5.5±1.3 to 1.6±1.1, the AOFAS score increased from 68.0±9.0 to 86.5±7.1, and the KP score improved from 65.2±14.0 to 86.9±8.1 after the operation, respectively; and all the three assessment scores improved significantly (all P<0.05). No cases presented postoperative complications such as non-union of the incision, skin necrosis, and infection, etc. This method is an ideal cure for pain on the external malleolus caused by subfibular ossicles, which has the advantages of less trauma and quick recovery.

Coronary CT angiography (CCTA) has been widely used in clinical diagnosis of coronary artery stenosis, but it lacks specificity in the diagnosis of myocardial ischemia. Integrating functional imaging such as CT myocardial perfusion (CT-MPI) and coronary flow reserve (FFR) into CCTA workflow can improve the diagnostic accuracy of CCTA for patients with coronary heart disease, improve the clinical treatment decision-making of patients with coronary heart disease and play a more important role in the prognosis judgment of patients, and may reduce the medical expenses of patients. However, there are still some problems in the clinical application of these CCTA functional imaging technologies, such as radiation dose and the accuracy of FFR-CT. Therefore, this article will review the clinical application value of CCTA functional imaging such as CT-MPI and FFR-CT in the diagnosis of coronary heart disease, the relationship between CT-MPI and FFR-CT, and the clinical problems faced by both.

Coronary CTA combined with CT myocardial perfusion imaging (CTP) is an emerging "one-stop" non-invasive imaging method for diagnosing the presence of myocardial ischemia in patients with suspected coronary heart disease. However, there are few studies on the distribution of normal myocardial perfusion in human body. To investigate the global and regional myocardial perfusion of the left ventricle at rest and under adenosine stress in asymptomatic women without a history of coronary artery disease, 34 patients with non-obstructive coronary artery disease (stenosis<50%) or middle-aged women with a history of coronary heart disease, exercise stress tests, and normal left ventricular function, who were subjected to resting versus adenosine-stressed static CTP scans using a 320-slice CT machine and evaluated semi-quantitatively. The study used the left ventricular myocardial 16-segment method to evaluate the myocardial perfusion reserve (MPR) and transmural perfusion ratio (TPR) of the left ventricle as a whole and in each region. The results showed that the distribution of blood perfusion in left ventricular myocardium was not uniform at rest and under load. The overall median MPR increased by 158% (144-176) on stress scan compared with that on resting scan, with the most increase in right coronary artery distribution (171%, P<0.02）。 The TPR values of each myocardial segment ranged from 0.93 to 1.26 and 0.99 to 1.13 at rest and stress scans, respectively, with the lowest value in the left ventricular subventricular interval. There were no significant differences in myocardial perfusion parameters between those with normal subepicardial coronary arteries and those with non-obstructive coronary artery lesions (bothP>0.05）。 Overall myocardial perfusion parameters were not associated with age or female menopausal status (bothP>0.05）。 This descriptive study provides perfusion data for the whole and different zones of the myocardium in a group of healthy middle-aged women.

Coronary computed tomography angiography (CTA) -based blood flow reserve fraction (CT-FFR) is a new technique to assess the physiological significance of coronary artery disease (CAD). CT-FFR is a powerful non-invasive diagnostic tool with significant potential in assessing myocardial ischemia, guiding treatment strategies, and providing prognostic information. Among them, HeartFlow's CT-FFR algorithm (USA, HeartFlow Company) has been validated in 3 multicenter clinical trials. However, HeartFlow's CT-FFR algorithm requires the use of off-site supercomputers for computation, which is time-consuming and expensive, which limits its wide application in clinical practice. Therefore, it makes great sense to develop a CT-FFR technique that can be performed in real time at a field workstation.