ABSTRACT
Introduction: Surgical studies evaluating a device or technology in comparison to an established surgical technique should accurately report all the important components of the surgical technique in order to reduce the risk of intervention bias. In the debate of visualization of the recurrent laryngeal nerve alone (VONA) versus intraoperative nerve monitoring (IONM) during thyroidectomy, surgical technique plays a key role in both strategies. Our aim was to investigate whether the surgical technique was considered as a risk of intervention bias by relevant meta-analyses and reviews and if steps of surgical intervention were described in their included studies. Methods: We searched PUBMED, CENTRAL-Cochrane library, PROSPERO and GOOGLE for reviews and meta-analyses focusing on the comparison of IONM to VONA in primary open thyroidectomy. Τhen, primary studies were extracted from their reference lists. We developed a typology for surgical technique applied in primary studies and a framework approach for the evaluation of this typology by the meta-analyses and reviews. Results: Twelve meta-analyses, one review (388,252 nerves at risk), and 84 primary studies (128,720 patients) were included. Five meta-analyses considered the absence of typology regarding the surgical technique as a source of intervention bias; 48 primary studies (57.14%) provided information about at least one item of the typology components and only 1 for all of them. Discussion: Surgical technique of thyroidectomy in terms of a typology is underreported in studies and undervalued by meta-analyses comparing VONA to IONM. This missing typology should be reconsidered in the comparative evaluation of these two strategies.
ABSTRACT
BACKGROUND: We investigated for the first time whether patients with recent-onset, uncomplicated hypertension and different hypertension phenotypes exhibit altered values of subendocardial viability ratio (SEVR), a surrogate measure of myocardial perfusion that correlates with the ratio of subendocardial to subepicardial blood flow. We additionally explored whether SEVR correlates with arterial stiffness in a population free from the long-term effects of essential hypertension. METHODS: Nontreated individuals free from any known health problems were classified as true hypertensives (THs), white-coat hypertensives (WCHs), masked hypertensives (MHs), and normotensives. SEVR was noninvasively calculated with applanation tonometry in the radial artery. Carotid-femoral pulse wave velocity, central and peripheral pulse pressure (PP), augmentation index, and central systolic/diastolic blood pressure (BP) were assessed with applanation tonometry. Total arterial compliance index was calculated with impedance cardiography. RESULTS: In a total of 150 participants, normotensive individuals exhibited the highest values of SEVR (162.9 ± 25.3%), whereas SEVR appeared to be similar in MHs (150.2 ± 22.1%), WCHs (148.1 ± 20.4%), and THs (149.9 ± 24.8%) (P = 0.017). In the univariate analysis, SEVR significantly correlated with central systolic BP, peripheral PP, and total arterial compliance index. The association between SEVR and both central (P = 0.017) and peripheral PP (P = 0.003) remained significant after adjustment for heart rate and other parameters. CONCLUSIONS: SEVR, an alternative tool to the invasive assessment of microvascular coronary perfusion, presents different values across patients with divergent BP phenotypes and correlated with arterial stiffness, even in the absence of overt cardiovascular disease. Future studies need to address the potential utility of this easily implementable marker as a screening test for myocardial ischemia.