Is inferior vena cava compression an alternative for valsalva maneuver in contrast-enhanced transcranial doppler？

Contrast-enhanced transcranial Doppler for the detection of right-to-left shunt: A new provocation method with a syringe-modified Valsalva maneuver

BACKGROUND

Contrast-enhanced transcranial Doppler (cTCD) study has been established as one of the most common investigations for detecting right-to-left shunt (RLS). Although the conventional Valsalva maneuver (c-VM) has been used to increase the sensitivity of cTCD for RLS, efforts are still needed to improve the detection rate further. We proposed a new provocation method with a syringe-modified Valsalva maneuver (sm-VM) during cTCD and compared the efficacy of this strategy with cTCD measured at resting and with the provocation of c-VM.

METHODS

Consecutive patients with suspicion of RLS who underwent cTCD in our institution between September 27, 2021, and April 1, 2022, were included in this study. Examination of cTCD was performed separately at the resting state and provoked with c-VM and sm-VM. The overall proportion of patients with RLS and their distribution with different RLS grades were compared.

RESULTS

A total of 389 patients (mean age: 49.37 years, male: 52.2%) were included in this study. The positive rate for RLS was significantly higher for cTCD detected with sm-VM than those detected at resting state and with c-VM (46.8% vs. 21.6% and 34.2%, all p < .05). Besides, cTCD detected with sm-VM was also associated with a higher proportion of patients with grade III RLS than those detected at resting state and with c-VM (11.3% vs. 1.8% and 0%, all p < .05).

CONCLUSIONS

Compared to cTCD detected at resting state and with c-VM, cTCD with sm-VM could further increase the positive detection rate of RLS.

Visualized Embolization of Inferior Vena Cava Thrombus During the Abdominal Compression Maneuver to Evaluate for a Patent Foramen Ovale

•IVC compression is an alternative to Valsalva to confirm the presence of a PFO. •A drawback of this method is reduced IVC compression in obese patients. •Use with caution in patients with low cardiac output and gastrointestinal diseases. •No complications while performing this maneuver have been reported. •We report visualized thrombus in the RA during the IVC compression maneuver.

Whether jugular venous reflux relates to more serious ischemic white matter lesions?

OBJECTIVE

To evaluate whether jugular venous reflux (JVR) relates to more serious ischemic white matter lesions (WMLs).

PATIENTS AND METHODS

Fifty cases were enrolled and divided into absent to mild ischemic WMLs group and moderate to severe ischemic WMLs group. Then the univariate and multivariate analyses were conducted to evaluate the relationship between JVR and moderate to severe ischemic WMLs, and a receiver operating characteristic (ROC) curve was used to evaluate the predictive value of JVR for moderate to severe ischemic WMLs.

RESULTS

There were 28 patients in the absent to mild ischemic WMLs group and 22 patients in the moderate to severe ischemic WMLs group. There was no significant difference between the two groups in gender, blood lipid indexes, proportions of diabetes, and abnormal deep cerebral veins (all p > 0.05). However, compared with the absent to mild ischemic WMLs group, the moderate to severe ischemic WMLs group was older and had a higher proportion of hypertension and JVR (p = 0.005; p < 0.001; p < 0.001, respectively). Multivariate logistic regression analysis showed that JVR was an independent risk factor for moderate to severe ischemic WMLs (OR = 17.679, 95 % CI: 3.056-102.286, p = 0.001). Furthermore, the area under curve of JVR combined with hypertension was 0.912 (p < 0.001), and the specificity of predicting moderate to severe ischemic WMLs was 92.9 %.

CONCLUSION

Our study suggested that JVR might relate to more severe ischemic WMLs.

Evaluation of right-to-left shunt on contrast-enhanced transcranial Doppler in patent foramen ovale-related cryptogenic stroke: Research based on imaging

BACKGROUND

Cardiogenic embolism caused by patent foramen ovale (PFO) is a common etiology of cryptogenic stroke (CS), particularly in young and middle-aged patients. Studies about right-to-left shunt (RLS) detection using contrast-enhanced transcranial Doppler (c-TCD) are numerous. According to the time phase and number of microbubbles detected on c-TCD, RLS can be classified and graded. We hypothesized that the characteristics of an infarction lesion on diffusion-weighted imaging differs when combining the type and grade of RLS on c-TCD in patients with PFO-related CS.

AIM

To explore the characteristics of infarction lesions on diffusion-weighted imaging when combining the RLS type and grade determined by c-TCD.

METHODS

We retrospectively evaluated CS patients from August 2015 to December 2019 at a tertiary hospital. In total, 111 PFO-related CS patients were divided according to whether RLS was permanent (microbubbles detected both at resting state and after the Valsalva maneuver) or latent (microbubbles detected only after the Valsalva maneuver) on c-TCD. Each group was subdivided into small, mild and large RLS according to the grade of shunt on c-TCD. A normal control group was composed of 33 patients who suffered from simple dizziness. Intragroup and intergroup differences were analyzed in terms of clinical, laboratory and diffusion-weighted imaging lesion characteristics. The correlation between RLS grade evaluated by c-TCD and size of PFO determined by transesophageal echocardiography were also analyzed.

RESULTS

In 111 patients with PFO-related CS, 68 had permanent RLS and 43 had latent RLS. Clinical characteristics and laboratory tests were not significantly different among the permanent RLS, latent RLS and normal control groups. The proportion of patients with multiple territory lesions in the permanent RLS group (50%) was larger than that in the latent RLS group (27.91%; P = 0.021). Posterior circulation was more likely to be affected in the latent RLS group than in the permanent RLS group (30.23% vs 8.82%, P = 0.004). Permanent-large and latent-large RLS were both more likely to be related to multiple (P_trend = 0.017 and 0.009, respectively), small (P_trend = 0.035 and 0.006, respectively) and cortical (P_trend = 0.031 and 0.033, respectively) lesions. The grade of RLS evaluated by c-TCD was correlated to the size of PFO determined by transesophageal echocardiography (r = 0.758, P < 0.001).

CONCLUSION

Distribution of the infarct suggested the possible type of RLS. Multiple, small and cortical infarcts suggest large RLS induced by a large PFO.