Nitroglycerin combined with NSAIDs for prevention of post-ERCP pancreatitis: A meta-analysis of prospective, randomized, controlled trials.

BACKGROUND: Acute pancreatitis is the most common complication of endoscopic retrograde cholangiopancreatography (ERCP), with an incidence of approximately 9.7% according to some literature reviews. Recent clinical guidelines propose that glyceryl trinitrate (GTN) can reduce the incidence of post-ERCP pancreatitis (PEP). However, currently, no guidelines provide an exact opinion on GTN and nonsteroidal anti-inflammatory drugs (NSAIDs) to prevent post-ERCP pancreatitis. OBJECTIVE: A meta-analysis was performed of published, full-length, randomized controlled trials (RCTs) evaluating the effects of prophylactic use of GTN, including GTN alone or GTN in combination with NSAIDs, on the prevention of PEP. METHODS: Literature searches were conducted using PubMed, Embase, Web of Science, and The Cochrane Library. Search terms included "endoscopic retrograde cholangiopancreatography" OR "ERCP," "OR 'PEP' OR 'post-endoscopic retrograde cholangiopancreatography pancreatitis', pancreatitis," "GTN" OR "glyceryl trinitrate" OR "nitroglycerin," "NSAIDs" OR "Nonsteroidal Anti-inflammatory Drugs" and limited to RCT. RESULTS: A total of 10 RCTs comprising 3240 patients undergoing ERCP were included. Meta-analysis revealed that the administration of GTN was associated with a significant reduction in the overall incidence of PEP. Moreover, PEP incidence was significantly lower in the GTN combined with the NSAIDs group than in the GTN alone group. GTN alone or GTN combined with NSAIDs may not reduce the severity of PEP (risk ratio = 0.64; 95% confidence interval: 0.41-0.99; P = .04). The difference in incidence between the 2 groups is 1.01% (6/594) in the GTN with NSAIDs group and 2.36% (14/592) in the placebo group. CONCLUSION: GTN has a significant benefit in preventing postoperative ERCP pancreatitis (P < .001). And neither GTN nor GTN plus NSAIDs reduces the incidence of non-mild ERCP postoperative pancreatitis. These conclusions need to be confirmed by high-quality randomized controlled studies with multicenter, large samples, and long-term follow-up.

Noninvasive assessment of human microvascular function in health and disease using incident dark-field microscopy.

Reduced peripheral microvascular reactivity is associated with an increased risk for major adverse cardiac events (MACEs). Tools for noninvasive assessment of peripheral microvascular function are limited, and existing technology is poorly validated in both healthy populations and patients with cardiovascular disease (CVD). Here, we used a handheld incident dark-field imaging tool (CytoCam) to test the hypothesis that, compared with healthy individuals (no risk factors for CVD), subjects formally diagnosed with coronary artery disease (CAD) or those with ≥2 risk factors for CAD (at risk) would exhibit impaired peripheral microvascular reactivity. A total of 17 participants (11 healthy, 6 at risk) were included in this pilot study. CytoCam was used to measure sublingual microvascular total vessel density (TVD), perfused vessel density (PVD), and microvascular flow index (MFI) in response to the topical application of acetylcholine (ACh) and sublingual administration of nitroglycerin (NTG). Baseline MFI and PVD were significantly reduced in the at-risk cohort compared with healthy individuals. Surprisingly, following the application of acetylcholine and nitroglycerin, both groups showed a significant improvement in all three microvascular perfusion parameters. These results suggest that, despite baseline reductions in both microvascular density and perfusion, human in vivo peripheral microvascular reactivity to both endothelial-dependent and -independent vasoactive agents remains intact in individuals with CAD or multiple risk factors for disease.NEW & NOTEWORTHY To our knowledge, this is the first study to comprehensively characterize in vivo sublingual microvascular structure and function (endothelium-dependent and -independent) in healthy patients and those with CVD. Importantly, we used an easy-to-use handheld device that can be easily translated to clinical settings. Our results indicate that baseline microvascular impairments in structure and function can be detected using the CytoCam technology, although reactivity to acetylcholine may be maintained even during disease in the peripheral microcirculation.

The Great Masquerade: Not All Coronary Artery Stenosis Are Created Equal.

We present the case of a 60-year-old male, with active smoking and cocaine use disorder, who reported progressive chest pain. Various anatomical and functional cardiac imaging, performed to further evaluate chest pain etiology, revealed changing severity and distribution of left main artery (LMA) stenosis, raising suspicion for vasospasm. Intracoronary nitroglycerin relieved the vasospasm, with resolution of the LMA pseudostenosis. A diagnosis of vasospastic angina (VA) led to starting appropriate medical therapy with lifestyle modification counselling. This case highlights VA, a frequently underdiagnosed etiology of angina pectoris. We discuss when to suspect VA, its appropriate work-up, and management.

Nitric oxide donor increases umbilical vein blood flow and fetal oxygenation in fetal growth restriction. A pilot study.

INTRODUCTION: To evaluate the maternal and fetal hemodynamic effects of treatment with a nitric oxide donor and oral fluid in pregnancies complicated by fetal growth restriction. METHODS: 30 normotensive participants with early fetal growth restriction were enrolled. 15 participants were treated until delivery with transdermal glyceryl trinitrate and oral fluid intake (Treated group), and 15 comprised the untreated group. All women underwent non-invasive assessment of fetal and maternal hemodynamics and repeat evaluation 2 weeks later. RESULTS: In the treated group, maternal hemodynamics improved significantly after two weeks of therapy compared to untreated participants. Fetal hemodynamics in the treated group showed an increase in umbilical vein diameter by 18.87 % (p < 0.01), in umbilical vein blood flow by 48.16 % (p < 0.01) and in umbilical vein blood flow corrected for estimated fetal weight by 30.03 % (p < 0.01). In the untreated group, the characteristics of the umbilical vein were unchanged compared to baseline. At the same time, the cerebro-placental ratio increased in the treated group, while it was reduced in the untreated group, compared to baseline values. The treated group showed a higher birthweight centile (p = 0.03) and a lower preeclampsia rate (p = 0.04) compared to the untreated group. DISCUSSION: The combined therapeutic approach with nitric oxide donor and oral fluid intake in fetal growth restriction improves maternal hemodynamics, which becomes more hyperdynamic (volume-dominant). At the same time, in the fetal circuit, umbilical vein flow increased and fetal brain sparing improved. Although a modest sample size, there was less preeclampsia and a higher birthweight suggesting beneficial maternal and fetal characteristics of treatment.

Managing Patients With Sympathetic Crashing Acute Pulmonary Edema (SCAPE) Using the SCAPE Treatment Protocol: A Case Series.

Pulmonary edema refers to the accumulation of excessive fluid in the alveolar walls and alveolar spaces of the lungs. It is a life-threatening condition with a high mortality rate and requires immediate assessment and management. Use of intravenous nitroglycerin has been advocated for such cases. The authors present a case series of 3 patients who presented to the emergency department with sympathetic crashing acute pulmonary edema (SCAPE) and were managed with high-dose intravenous nitroglycerin and bilevel positive airway pressure support using the SCAPE treatment protocol, leading to early correction of blood pressure, avoidance of endotracheal intubation, and no episodes of hypotension or rebound hypertension. The authors recommend emergency physicians utilize the SCAPE treatment protocol while managing patients with SCAPE.

Nitroglycerin to Ameliorate Coronary Artery Spasm During Focal Pulsed-Field Ablation for Atrial Fibrillation.

BACKGROUND: In treating atrial fibrillation, pulsed-field ablation (PFA) has comparable efficacy to conventional thermal ablation, but with important safety advantages: no esophageal injury or pulmonary vein stenosis, and rare phrenic nerve injury. However, when PFA is delivered in proximity to coronary arteries using a pentaspline catheter, which generates a broad electrical field, severe vasospasm can be provoked. OBJECTIVES: The authors sought to study the vasospastic potential of a focal PFA catheter with a narrower electrical field and develop a preventive strategy with nitroglycerin. METHODS: During atrial fibrillation ablation, a focal PFA catheter was used for cavotricuspid isthmus ablation. Angiography of the right coronary artery (some with fractional flow reserve measurement) was performed before, during, and after PFA. Beyond no nitroglycerin (n = 5), and a few testing strategies (n = 8), 2 primary nitroglycerin administration strategies were studied: 1) multiple boluses (3-2 mg every 2 min) into the right atrium (n = 10), and 2) a bolus (3 mg) into the right atrium with continuous peripheral intravenous infusion (1 mg/min; n = 10). RESULTS: Without nitroglycerin, cavotricuspid isthmus ablation provoked moderate-severe vasospasm in 4 of 5 (80%) patients (fractional flow reserve 0.71 ± 0.08). With repetitive nitroglycerin boluses, severe spasm did not occur, and mild-moderate vasospasm occurred in only 2 of 10 (20%). Using the bolus + infusion strategy, severe and mild-moderate spasm occurred in 1 and 3 of 10 patients (aggregate 40%). No patient had ST-segment changes. CONCLUSIONS: Ablation of the cavotricuspid isthmus using a focal PFA catheter routinely provokes right coronary vasospasm. Pretreatment with high doses of parenteral nitroglycerin prevents severe spasm.

Association of cumulative low-density lipoprotein cholesterol exposure with vascular function.

BACKGROUND: The relationship between cumulative low-density lipoprotein cholesterol (LDL-C) exposure and progression of atherosclerosis remains uncertain. OBJECTIVE: The aim of this study was to determine the relationship between cumulative LDL-C level and flow-mediated vasodilation (FMD), nitroglycerine-induced vasodilation (NID) and the presence of plaque in the common carotid artery (CCA). METHODS: This was a cross-sectional study. We measured FMD in 8208 subjects, NID in 1822 subjects, and CCA plaque in 591 subjects who were not taking lipid-lowering drugs. The subjects were divided into four groups based on cumulative LDL-C exposure: <4000 mg·year/dL, 4000-4999 mg·year/dL, 5000-5999 mg·year/dL, and ≥6000 mg·year/dL. RESULTS: The odds ratio of the lower quartile of FMD in the cholesterol-year-score <4000 mg·year/dL group was significantly higher than the odds ratios in the other groups. The odds ratio of the lower quartile of NID in the <4000 mg·year/dL group was significantly higher than the odds ratios in the 5000-5999 mg·year/dL and ≥6000 mg·year/dL groups. The odds ratio of the prevalence of CCA plaque in the <4000 mg·year/dL group was significantly higher than that in the ≥6000 mg·year/dL group. CONCLUSIONS: Endothelial dysfunction occurred from cumulative LDL-C exposure of 4000 mg·year/dL, vascular smooth muscle dysfunction occurred from cumulative LDL-C exposure of 5000 mg·year/dL, and prevalence of CCA plaque occurred from cumulative LDL-C exposure of 6000 mg·year/dL. CLINICAL TRIAL REGISTRY INFORMATION: http://www.umin.ac.jp (UMIN000012950, UMIN000012951, and UMIN000012952, UMIN000003409).

High-dose versus low-dose intravenous nitroglycerine for sympathetic crashing acute pulmonary edema: a randomised controlled trial.

OBJECTIVES: Sympathetic crashing acute pulmonary edema (SCAPE) is a subset of heart failure with a dramatic presentation. The unique physiology of this condition requires a different management strategy from the conventional practice. The trial objective was to compare the efficacy of high-dose and low-dose GTN in patients with SCAPE. METHODS: This was an open-label randomised control trial conducted in a tertiary care teaching hospital in India from 11 November 2021 to 30 November 2022. Consenting participants were randomised to high-dose GTN or conventional low-dose GTN. The primary outcome was symptom resolution at 6 hours and 12 hours. Secondary outcomes included intubation rates, admission rates, length of hospital stay, and any short-term adverse effects of GTN and major adverse cardiac events (MACE) at 30 days. RESULTS: Fifty-four participants were included (26 high-dose GTN, 26 low-dose GTN). At 6 hours, symptom resolution was seen in 17 patients (65.4%) in the 'high-dose' group, compared with 3 (11.5%) in the 'low-dose' group (p<0.001). At 12 hours, 88.5% of patients had a clinical resolution in the 'high-dose' arm versus 19.5% in 'low-dose' arm . The low-dose group had longer median hospital stay (12 hours vs 72 hours), more frequent MACE (3.8% vs 26.9%, p=0.02) and a higher intubation rate (3.8% vs 19.2%, p=0.08). The only short-term adverse effect seen was a headache in both the groups. CONCLUSION: In SCAPE, patients receiving high-dose GTN (>100 mcg/min) had earlier symptom resolution compared with the conventional 'low dose' GTN without any significant adverse effects. TRIAL REGISTRATION: Clinical trial registry of India (CTRI/2021/11/037902).

Impact of Sublingual Nitroglycerin on the Assessment of Computed Tomography-derived Fractional Flow Reserve: An Intraindividual Comparison Study.

OBJECTIVE: The aim of this study was to investigate the impact of nitroglycerin (NTG) on the assessment of computed tomography-derived fractional flow reserve (CT-FFR). MATERIALS AND METHODS: Seventy-seven patients with suspected coronary artery disease were recruited, and they underwent computed tomography angiography (CCTA) before and after NTG administration. The CT-FFRs were compared at 2 CCTAs. The difference was compared using the Wilcoxon signed rank test. Patients were divided into normal and stenosis groups according to CCTA results. Vessels in the stenosis group were further divided into different groups based on coronary artery calcium score (CACS) and stenosis degree. The poststenotic CT-FFR differences before and after NTG (DCT-FFR) were calculated to evaluate the impact of stenosis degree and CACS. Terminal CT-FFRs derived from CCTAs before and after NTG in total and vessel-specific levels were compared in the normal group. RESULTS: Of 47 patients in the stenosis group, poststenotic CT-FFR was significantly increased after NTG at per-vessel level. By taking CT-FFR of 0.75 or lower as the threshold, 5 and 4 patients showed abnormal CT-FFR before and after NTG, respectively. No significant differences were noted among the various stenosis degree and CACS groups regarding DCT-FFR. Of 30 patients in the normal group, terminal CT-FFR was significantly increased after NTG in total level and vessel-specific level of left anterior descending and right coronary artery, but not in the left circumflex. CONCLUSIONS: Both post lesion and distal vessel CT-FFR significantly improved after the administration of GTN with the degree of change not affected by stenosis severity or CACS.

Perianal Application of Glyceryl Trinitrate Ointment Versus Tocopherol Acetate Ointment in the Treatment of Chronic Anal Fissure: A Randomized Clinical Trial.

BACKGROUND: Medical treatment, including glyceryl trinitrate ointment, represents the first step for the management of chronic anal fissure. However, glyceryl trinitrate ointment is associated with headache and, consequently, a high withdrawal rate of the treatment. OBJECTIVE: The aim of the present study was to evaluate the effect of the topical application of tocopherol acetate ointment on pain relief and chronic anal fissure epithelialization, comparing it with the effect of a standard treatment with glyceryl trinitrate ointment. DESIGN: This is a 2-parallel-group, single-center, randomized controlled, intent-to-treat clinical trial. SETTINGS: This study was conducted at the Garcilaso Clinic affiliated with Universidad Alfonso X (Madrid, Spain). PATIENTS: Patients with chronic anal fissure were selected. INTERVENTIONS: Patients were randomly assigned into 2 groups: patients receiving tocopherol acetate ointment and patients receiving glyceryl trinitrate ointment. MAIN OUTCOME MEASURES: The primary end point was quantification of anal pain 8 weeks after beginning the treatment as measured by a Visual Analogue Scale ranging from 0 to 100 mm. The secondary end points were the healing rate (during the treatment period of 8 weeks) and the recurrence rate. RESULTS: One hundred sixty consecutive patients were treated, 80 in each group. By 8 weeks after treatment, mean anal pain score declined by 56.2 mm in the glyceryl trinitrate ointment group compared with a mean anal pain score decline of 67.1 mm in the tocopherol acetate ointment group (mean difference, 10.9 mm (95% CI, 4.3-18.6); p = 0.018). Sixteen weeks after finishing the therapy, the recurrence rate was 13.2% in the glyceryl trinitrate ointment group vs 2.9 in the tocopherol acetate ointment group (p = 0.031). LIMITATIONS: Limitations of the study include the absence of manometric measurements of the internal anal sphincter before and after the treatments and the use of glyceryl trinitrate ointment as an active comparator, whereas calcium channel blockers are actually the standard treatment. CONCLUSIONS: Anal pain was significantly lower in the tocopherol acetate ointment group than in the glyceryl trinitrate ointment group at 8 weeks after treatment. Tocopherol acetate ointment achieved a greater healing rate and a lower recurrence rate 16 weeks after finishing the treatment. See Video Abstract at http://links.lww.com/DCR/B751. REGISTRATION: URL: https://www.clinicaltrials.gov; Identifier: NCT03787030.APLICACIÓN PERIANAL DE POMADA DE TRINITRATO DE GLICERILO FRENTE A LA POMADA DE ACETATO DE TOCOFEROL EN EL TRATAMIENTO DE LA FISURA ANAL CRÓNICA: UN ENSAYO CLÍNICO ALEATORIZADOANTECEDENTES:El tratamiento médico, incluida la pomada de trinitrato de glicerilo, representa el primer paso para el tratamiento de la fisura anal crónica. Sin embargo, la pomada de trinitrato de glicerilo se asocia con cefalea y, en consecuencia, una alta tasa de cancelación del tratamiento.OBJETIVO:El objetivo del presente estudio fue evaluar el efecto de la aplicación tópica de pomada de acetato de tocoferol en el alivio del dolor y la epitelización de la fisura anal crónica, comparándolo con el efecto de un tratamiento estándar con pomada de trinitrato de glicerilo.DISEÑO:Ensayo clínico con intención de tratar controlado, aleatorizado, de un solo centro, con dos grupos paralelos.ESCENARIO:Clínica Garcilaso adscrita a la Universidad Alfonso X (Madrid, España).PACIENTES:Pacientes con fisura anal crónica.INTERVENCIONES:Los pacientes fueron aleatorizados en 2 grupos: pacientes que recibieron pomada de acetato de tocoferol y pacientes que recibieron pomada de trinitrato de glicerilo.PRINCIPALES MEDIDAS DE RESULTADO:El criterio de valoración principal fue la cuantificación del dolor anal 8 semanas después de comenzar el tratamiento, medido por la escala analógica visual que varía de 0 a 100 mm. Los criterios de valoración secundarios fueron la tasa de curación (durante el período de tratamiento de 8 semanas) y la tasa de recurrencia.RESULTADOS:Se trataron ciento sesenta pacientes consecutivos, 80 en cada grupo. A las ocho semanas después del tratamiento, la puntuación media de dolor anal se redujo en 56.2 mm en el grupo de pomada de trinitrato de glicerilo en comparación con una disminución de la puntuación de dolor anal medio de 67.1 mm en el grupo de pomada de acetato de tocoferol (diferencia media: 10.9 mm (intervalo de confianza del 95%; 4.3 a 18.6; p = 0.018) Dieciséis semanas después de finalizar la terapia, la tasa de recurrencia fue del 13.2% en el grupo de pomada de trinitrato de glicerilo frente a 2.9 en el grupo de pomada de acetato de tocoferol (p = 0.031).LIMITACIONES:Ausencia de medidas manométricas del esfínter anal interno antes y después de los tratamientos. Ungüento de trinitrato de glicerilo como comparador activo, mientras que los bloqueadores de los canales de calcio son en realidad el tratamiento estándar de oro.CONCLUSIONES:El dolor anal fue significativamente menor en el grupo de ungüento de acetato de tocoferol que en el grupo de ungüento de trinitrato de glicerilo a las 8 semanas después del tratamiento. La pomada de acetato de tocoferol logró una mayor tasa de curación y una menor tasa de recurrencia 16 semanas después de finalizar el tratamiento. Consulte Video Resumen en http://links.lww.com/DCR/B751. (Traducción-Dr. Jorge Silva Velazco).

Diagnostic and prognostic role of nitroglycerin-induced dilation in patients with suspected vasospastic angina, combined with ergonovine provocation test.

The diagnostic and prognostic role of nitroglycerin-induced dilation (NID) combined with ergonovine provocation test in patients with suspected VSA patients is not clear. A total of 438 consecutive patients who underwent the ergonovine provocation test for the diagnosis of vasospastic angina (VSA) were enrolled. Patients with VSA (n = 52) had a significantly greater coronary response to ergonovine (- 84.3 ± 10.5% vs. - 38.4 ± 17.9%, p < 0.001) and NID (26.3 ± 31.0% vs. 12.5 ± 19.0%, p < 0.001) than non-VSA patients. However, positive NID (more than 13.8% dilation, n = 170) showed a poor accuracy (AUC 0.64 [95% CI: 0.56-0.73], p = 0.001, sensitivity 60.4%, specificity 61.3%) for the diagnosis of VSA by ergonovine provocation test. Major adverse cardiovascular events (MACE) occurred more frequently in the VSA group than in the non-VSA group (9.6% vs. 2.2%, p = 0.006). In addition, the positive NID group showed a lower rate of MACE than the negative NID group (1.2% vs. 4.3%, p = 0.021). Interestingly, the group of VSA with negative NID had poor prognosis than any other combinations (Log-rank, p < 0.0001). Although NID had a limited role in the detection of VSA defined by ergonovine provocation test, NID combined with the ergonovine provocation test has an additive prognostic role in the clinical outcomes in patients with suspected VSA.

SCFA Treatment Alleviates Pathological Signs of Migraine and Related Intestinal Alterations in a Mouse Model of NTG-Induced Migraine.

BACKGROUND: There is a growing realization that the gut-brain axis signaling is critical for maintaining the health and homeostasis of the Central Nervous System (CNS) and the intestinal environment. The role of Short-Chain Fatty Acids (SCFAs), such as Sodium Propionate (SP) and Sodium Butyrate (SB), has been reported to counteract inflammation activation in the central and Enteric Nervous System (ENS). METHODS: In this study, we evaluated the role of the SCFAs in regulating the pathophysiology of migraine and correlated dysregulations in the gut environment in a mouse model of Nitroglycerine (NTG)-induced migraine. RESULTS: We showed that, following behavioral tests evaluating pain and photophobia, the SP and SB treatments attenuated pain attacks provoked by NTG. Moreover, treatments with both SCFAs reduced histological damage in the trigeminal nerve nucleus and decreased the expression of proinflammatory mediators. Ileum evaluation following NTG injection reported that SCFA treatments importantly restored intestinal mucosa alterations, as well as the release of neurotransmitters in the ENS. CONCLUSIONS: Taken together, these results provide evidence that SCFAs exert powerful effects, preventing inflammation through the gut-brain axis, suggesting a new insight into the potential application of SCFAs as novel supportive therapies for migraine and correlated intestinal alterations.

The Effects of Intravenous Nitroglycerin Bolus Doses in Reducing Hemodynamic Responses to Laryngoscopy and Endotracheal Intubation.

BACKGROUND: Hemodynamic responses to laryngoscopy and endotracheal intubation are transient in most patients. However, in some patients with a history of heart disease, systemic hypertension, or cerebrovascular disease, these may lead to dangerous complications. This study is aimed at determining the effectiveness of intravenous nitroglycerin bolus doses in reducing hemodynamic responses to laryngoscopy and endotracheal intubation. Material and Method. In this double-blind randomized controlled trial, 78 patients aged 18 to 65 years were randomly divided into three groups: 1 µg/kg dose of nitroglycerin (first group), 2 µg/kg dose of nitroglycerin (second group), and normal saline or placebo (third group). 26 samples were allocated for each group. Patients' hemodynamic responses to laryngoscopy and endotracheal intubation were measured at different times. Data were analyzed using SPSS V 16. RESULTS: Patients in the three study groups were similar in terms of age, sex, and weight. There was no significant difference between the mean saturation of peripheral oxygen (SPO2) and the mean heart rate between the three groups before endotracheal intubation and 1 to 10 minutes after intubation (P > 0.05). The difference of mean arterial blood pressure between study groups was only significant in the first and fifth minutes after intubation. Mean systolic and diastolic blood pressure in the first, third, and fifth minutes after intubation was significantly lower in the intervention groups than the control group (P < 0.05). However, no significant difference was observed between the intervention groups. The frequency of systolic blood pressure decrease was significantly different in the first and fifth minutes after intubation in the three study groups (P < 0.05). CONCLUSION: Bolus doses of 1 and 2 µg/kg nitroglycerin in noncardiac elective surgery prevents the increase of mean systolic, diastolic, and arterial blood pressure but has no significant effect on heart rate after intubation.

Acute effects of sublingual nitroglycerin on cardiovagal and sympathetic baroreflex sensitivity.

The effects of nitroglycerin (glyceryl trinitrate, GTN) on baroreflex sensitivity (BRS) are incompletely understood. Moreover, there are no reports evaluating the acute responses in both the sympathetic BRS (SBRS) and the cardiovagal BRS (CBRS) to the administration of sublingual GTN. We hypothesized that sublingual GTN modulates both CBRS and SBRS. In 10 healthy subjects, beat-to-beat heart rate (HR), blood pressure (BP), and muscle sympathetic nerve activity (MSNA) were recorded before and for 10 min after sublingual administration of GTN 0.4 mg. SBRS was evaluated from the relationship between spontaneous variations in diastolic BP and MSNA. CBRS was assessed with the sequence technique. These variables were assessed during baseline, during 3rd-6th min (post A), and 7th-10th min (post B) after GTN administration. Two min after GTN administration, MSNA increased significantly and remained significantly elevated during recording. Compared with baseline, CBRS decreased significantly (post A: 12.9 ± 1.6 to 7.1 ± 1.0 ms/mmHg, P < 0.05), whereas SBRS increased significantly (post A: 0.8 ± 0.2 to 1.5 ± 0.2 units·beat-1·mmHg-1, P < 0.05) with an upward shift of the operating point. There were no differences in these variables between posts A and B. A clinical dose of GTN increased MSNA rapidly through effects on both CBRS and SBRS. These effects should be kept in mind when nitrates are used to clinically treat chest pain and acute coronary syndromes and used as vasodilators in experimental settings.

Adverse events after prehospital nitroglycerin administration in a nationwide registry analysis.

OBJECTIVE: Nitroglycerin (NTG) is a vasodilator used in the prehospital setting with chest pain patients. Potential adverse effects include hypotension, bradycardia or tachycardia, and mental status change. However, it is unclear which factors, if any, are associated with patients having an adverse event after receiving NTG. The objective of this study was to determine demographic and clinical factors associated with adverse events after prehospital NTG administration. METHODS: The ESO Data Collaborative (Austin, TX), containing records from 1322 EMS agencies, was queried for 911 encounters where NTG was administered to patients ≥18 years old by EMS. Adverse event outcomes were defined as a new systolic blood pressure (SBP) < 90, heart rate (HR) < 50 or > 120, mean arterial pressure (MAP) < 65, or change in mental status following NTG administration. Descriptive statistics and logistic regression models adjusting for age, sex, race, ethnicity, intravenous (IV) access, and initial vital signs were used to assess for adverse event-related factors. RESULTS: Among 80,760 encounters, the mean age was 61 (IQR 50-72), with 52% males, 71% white race, and 7% Hispanic ethnicity. Adverse events occurred in 7% of encounters. Adverse events were found to be less common among Black patients (OR = 0.74, 95%CI:0.69-0.80). IV access obtained prior to NTG administration was associated with fewer adverse events (OR = 0.92, 95%CI:0.85-0.99). Increasing age (OR = 1.02, 95%CI:1.01-1.02) and HR (OR = 1.03, 95%CI:1.02-1.03) were associated with increased odds of adverse events while SBP (OR = 0.99, 95%CI:0.98-0.99) was inversely associated. CONCLUSIONS: Adverse events following prehospital NTG administration were rare, especially in patients with an SBP > 110 and a HR < 100, and less frequent in those with existing IV access. Demographics were not found to be clinically significant.

Quantifying the Effect of Topical Nitroglycerin on Random Pattern Flap Perfusion in a Rodent Model: An Application of the ViOptix Intra.Ox for Dynamic Flap Perfusion Assessment and Salvage.

BACKGROUND: Near-infrared spectroscopy can detect changes in tissue oxygenation postoperatively that predict flap necrosis. The authors hypothesized that this technology can be applied along with topical nitroglycerin to measure an improvement in tissue oxygenation that correlates with tissue salvage. METHODS: Dorsal, random pattern flaps measuring 10 × 3 cm were raised using Sprague-Dawley rats. Tissue oxygenation was measured after flap elevation in 10 locations using the ViOptix Intra.Ox. Animals were divided into three groups that received 30 mg of topical nitroglycerin daily, twice-daily, or not at all. Oxygenation measurements were repeated on postoperative day 1 and animals were euthanized on day 7 and evaluated for tissue necrosis. RESULTS: Tissue necrosis was greatest in controls (51.3 mm) compared to daily (28.8 mm) and twice-daily nitroglycerin (18.8 mm; p = 0.035). Three flap perfusion zones were identified: healthy (proximal, 50 mm), necrotic (distal, 20 mm), and watershed. Immediate postoperative tissue oxygenation was highest in healthy tissue (57.2 percent) and decreased to 33.0 and 19.3 percent in the watershed and necrotic zones, respectively (p < 0.001). One day after treatment with nitroglycerin, oxygenation in the healthy zone did not increase significantly (mean difference, -1.5 percent). The watershed (17.8 percent; p < 0.001) and necrotic zones (16.3 percent; p <0.001) did exhibit significant improvements that were greater than those measured in control tissues (7.9 percent; both p < 0.001). CONCLUSIONS: Serial perfusion assessment using the ViOptix Intra.Ox measured a significant improvement in flap oxygenation after treatment with topical nitroglycerin. Within the watershed area of the flap, this increase in tissue oxygenation was associated with the salvage of ischemic tissue.

Cardiovascular magnetic resonance image analysis and mechanism study for the changes after treatments for primary microvascular angina pectoris.

ABSTRACT: Most cases of primary microvascular angina pectoris (PMVA) are diagnosed clinically, but the etiology and pathological mechanisms are unknown. The effect of routine clinical medications is minimal, and PMVA can progress to serious cardiovascular events. To improve the diagnosis and effective treatment of this disease, this study was designed to diagnose PMVA via cardiovascular magnetic resonance (CMR) and the coronary angiography thrombolysis in myocardial infarction (TIMI) blood flow grade, as well as to analyze vascular endothelial function to elucidate the pathogenesis of PMVA and compare the effects of routine clinical medications.The present randomized controlled trial including a parallel control group will be conducted on 63 PMVA patients in our cardiovascular department. The patients will be selected and randomly divided into the control, diltiazem, and nicorandil groups. The control group will be administered routine drug treatments (aspirin, atorvastatin, betaloc ZOK, perindopril, and isosorbidemononitrate sustained-release tablets). The diltiazem group will be additionally treated with 90 mg qd diltiazem sustained-release capsules. The nicorandil group was additionally given 5 mg tid nicorandil tablets. Coronary angiography will be performed before treatment, the severity and frequency of chest pain will be evaluated before and after 9 months of treatment, and homocysteine and von Willebrand factor levels will be measured. Electrocardiography, echocardiography, dynamic electrocardiography, a treadmill exercise test, and CMR will be performed. Sex, age, body mass index, complications, smoking, and family history will also be recorded. The SPSS19.0 statistical software package will be used to analyze the data. The measurements will be expressed as the mean ±â€Šstandard deviation. Measurement data will be compared between the groups using Student's t-test. A relative number description will be used for the counting data, and the chi-squaretest will be used to compare the groups. A multivariate logistic regression analysis will be performed A P-value < .05 will be considered significant.The direct indices (CMR and coronary angiographic TIMI blood flow grade) may improve after adding diltiazem or nicorandil during routine drug treatments (such as aspirin, statins, and nitrates) in PMVA patients, and indirect indices (homocysteine and von Willebrand factor levels) may be reduced. TRIAL REGISTRATION: Chinese Clinical Trial Registry (http://www.chictr.org.cn/showprojen.aspx?proj=41894), No. CHiCTR1900025319, Registered on August 23, 2019; pre initiation.

Myocardial protective effect of intracoronary administration of nicorandil and alprostadil via targeted perfusion microcatheter in patients undergoing elective percutaneous coronary intervention: A randomized controlled trial.

BACKGROUND: The aim of the study was to evaluate the efficacy of nicorandil and alprostadil on myocardial protection in patients undergoing elective percutaneous coronary intervention (PCI). METHODS: In this prospective, single-blinded, randomized controlled study, 90 consecutive patients scheduled for elective PCI for de novo coronary lesions were assigned to the nicorandil, alprostadil, and nitroglycerin groups in a 1:1:1 ratio. Drugs were administered intracoronary via a targeted perfusion microcatheter. The primary endpoint was the thrombolysis in myocardial infarction (TIMI) myocardial perfusion frame count (TMPFC). Additionally, the corrected TIMI frame count (cTFC), TIMI myocardial perfusion grade (TMPG), and incidence of periprocedural myocardial injury (PMI) were assessed. RESULTS: Both nicorandil and alprostadil were significantly effective in reducing TMPFC (114.6 ±â€Š33.7 vs 93.4 ±â€Š30.9, P = .016; 114.3 ±â€Š34.3 vs 94.7 ±â€Š33.3, P = .029, respectively). Similar findings were observed in the improvement of cTFC (20.3 ±â€Š10.5 vs 13.5 ±â€Š5.0, P = .003; 20.2 ±â€Š7.4 vs 15.2 ±â€Š5.2, P = .003, respectively) and percentage of TMPG 3 (100% vs 82.8%, P = .052; 83.3% vs 96.7%, P = .196, respectively); whereas, nitroglycerin produced a limited effect on TMPFC (114.4 ±â€Š30.9 vs 112.1 ±â€Š31.9, P = .739), cTFC (19.4 ±â€Š7.2 vs 19.3 ±â€Š7.2, P = .936), and percentage of TMPG 3 (86.7% vs 86.7%, P = 1.000). No significant difference was found in the incidence of PMI (16.7% vs 16.0% vs 27.6%, P = .537), though it was comparatively lower in the nicorandil and alprostadil groups. Furthermore, the intracoronary administration of nicorandil and alprostadil had a mild effect on blood pressure and heart rate. CONCLUSIONS: The intracoronary administration of nicorandil and alprostadil via a targeted perfusion microcatheter was more effective in improving myocardial perfusion in patients undergoing elective PCI than nitroglycerin.