Chronic total occlusion rotational atherectomy (CTO RA) versus non-CTO RA in coronary artery disease: A meta-analysis of clinical outcomes and complications.

Background: Chronic total occlusion rotational atherectomy (CTO RA) is an emerging intervention in coronary artery disease (CAD), although data comparing its outcomes and complications with non-CTO RA are scarce. We sought to evaluate the outcomes of RA in CTO lesions compared to those in non-CTO lesions by performing a meta-analysis. Methods: We conducted a systematic review and meta-analysis of studies comparing the clinical outcomes and complications between CTO RA and non-CTO RA in patients with CAD. We searched PUBMED, CINAHL, EMBASE and Cochrane Central Register of Clinical Trials for any studies that compared the outcomes of RA in CTO and non-CTO lesions. The outcomes analyzed included in-hospital major adverse cardiovascular events (MACE), target vessel revascularization (TVR), angiographic success, procedural success, periprocedural complications, coronary perforation, and all-cause mortality. Results: Four studies with a total of 1868 patients were included, spanning from 2018 to 2022, from Germany, Taiwan, and Korea. The median age of included patients was 71. The rate of the pooled results indicated a moderate, non-significant increase in in-hospital MACE and TVR for CTO RA compared to non-CTO RA. There was a small, non-significant decrease in angiographic and procedural success in CTO RA compared to non-CTO RA. CTO RA was associated with a non-significant increase in periprocedural complications and a significant increase in coronary perforation compared to non-CTO RA. All-cause mortality showed a non-significant increase in the CTO RA group. Conclusion: This meta-analysis provides evidence that while CTO RA may be associated with a higher risk of coronary perforation, the risk of other outcomes including MACE, TVR, and all-cause mortality is not significantly different compared to non-CTO RA. More research is needed to further understand these relationships and to optimize treatment strategies in patients with CAD undergoing CTO RA.

Rotational Atherectomy in Acute Coronary Syndrome: A Meta-Analysis.

BACKGROUND: The use of rotational atherectomy (RA) in percutaneous coronary intervention (PCI) of acute coronary syndrome (ACS) is considered relatively contraindicated. There have been several observational studies showing RA use in ACS, however, no systemic studies have been undertaken. We sought to evaluate the feasibility and outcomes of RA PCI in ACS by performing a meta-analysis. METHODS: We searched PUBMED, EMBASE, CINAHL, and Cochrane Central Register of Clinical Trials for any studies that evaluated the role of RA PCI in ACS. The outcomes analyzed were all-cause mortality, cardiac mortality, short and long-term major adverse cardiac events (MACE), procedural complications and cardiac perforations. RESULTS: There was a total of 8 retrospective studies with a total population of 1237 with a median follow up of 23 months. The median age of the included patient was 73. Angiographic success rate was 97.4%. The rate of all-cause mortality and cardiac mortality were 5% (range 1-12%, p < 0.001, I2 = 92%) and 2% (range 0-5%, P = 0.03, I2 = 58%) respectively. In-hospital MACE and long-term MACE were 7% (range 3-13%, p < 0.001, I2 = 87%) and 29% (range 21-37%, p = 0.21, I2 = 34%) respectively. The incidence of total procedural complications was noted to be 7% (range 2-14%, p < 0.001, I2 = 90%). Rate of perforation was 1% (range 0-1%, p = 0.9, I2 = 0%). CONCLUSION: Our results show that RA PCI is feasible in ACS with comparable procedural complications and short-term MACE, but with a higher long-term MACE rate compared to RA PCI in routine cases.

Skin sympathetic nerve activity as a biomarker of fitness.

BACKGROUND: Exercise stress testing is frequently used to expose cardiac arrhythmias. Aerobic exercise conditioning has been used as a nonpharmacologic antiarrhythmic intervention. OBJECTIVE: The purpose of this study was to test the hypothesis that noninvasively recorded skin sympathetic nerve activity (SKNA) is increased during exercise and that SKNA response varies according to fitness levels. METHODS: Oxygen consumption (VO2) and SKNA were recorded in 39 patients undergoing an incremental exercise test. Patients were grouped by 5 levels of fitness based on age, sex, and VO2max. RESULTS: With exercise, all patients had a significant increase in average SKNA (aSKNA) (1.58 ± 1.12 µV to 4.50 ± 3.06 µV, P = .000) and heart rate (HR) (87.40 ± 20.42 bpm to 154.13 ± 16.82 bpm, P = .000). A mixed linear model of aSKNA was used with fixed effects of fitness, exercise time, and recovery time, and random effects of subject level intercept and slopes for exercise time and recovery times. The poor fitness group had significantly higher aSKNA than the other groups (P = .0273). For all subjects studied, aSKNA increased by 5% per minute with progression of exercise and decreased by 15% per minute with progression of recovery. The fitness variable encodes information on both comorbidities and body mass index (BMI). Once fitness level is known, comorbidities and BMI are not significantly associated with aSKNA. In all groups, aSKNA positively correlated with HR (R2 = 0.47 ± 0.23) and VO2 (R2 = 0.68 ± 0.25). CONCLUSION: Fitness level determines the magnitude and time course of SKNA increase during exercise. SKNA may be a useful fitness biomarker in exercise stress testing.

Skin sympathetic nerve activity as a biomarker for neurologic recovery during therapeutic hypothermia for cardiac arrest.

BACKGROUND: Targeted temperature management (TTM) improves neurologic outcome after cardiac arrest. However, better neurologic prognostication is needed. OBJECTIVE: The purpose of this study was to test the hypothesis that noninvasive recording of skin sympathetic nerve activity (SKNA) and its association with heart rate (HR) during TTM may serve as a biomarker of neurologic status. METHODS: SKNA recordings were analyzed from 29 patients undergoing TTM. Patients were grouped based on Clinical Performance Category (CPC) score into group 1 (CPC 1-2) representing a good neurologic outcome and group 2 (CPC 3-5) representing a poor neurologic outcome. RESULTS: Of the 29 study participants, 18 (62%) were deemed to have poor neurologic outcome. At all timepoints, low average skin sympathetic nerve activity (aSKNA) was associated with poor neurologic outcome (odds ratio 22.69; P = .002) and remained significant (P = .03) even when adjusting for presenting clinical factors. The changes in aSKNA and HR during warming in group 1 were significantly correlated (ρ = 0.49; P <.001), even when adjusting for corresponding temperature and mean arterial pressure measurements (P = .017), whereas this correlation was not observed in group 2. Corresponding to high aSKNA, there was increased nerve burst activity during warming in group 1 compared to group 2 (0.739 ± 0.451 vs 0.176 ± 0.231; P = .013). CONCLUSION: Neurologic recovery was retrospectively associated with SKNA. Patients undergoing TTM who did not achieve neurologic recovery were associated with low SKNA and lacked a significant correlation between SKNA and HR. These preliminary results indicate that SKNA may potentially be a useful biomarker to predict neurologic status in patients undergoing TTM.

Skin sympathetic nerve activity as a biomarker for syncopal episodes during a tilt table test.

BACKGROUND: Autonomic imbalance is the proposed mechanism of syncope during a tilt table test (TTT). We have recently demonstrated that skin sympathetic nerve activity (SKNA) can be noninvasively recorded using electrocardiographic electrodes. OBJECTIVE: The purpose of this study was to test the hypothesis that increased SKNA activation precedes tilt-induced syncope. METHODS: We studied 50 patients with a history of neurocardiogenic syncope undergoing a TTT. The recorded signals were band-pass filtered at 500-1000 Hz to analyze nerve activity. RESULTS: The average SKNA (aSKNA) value at baseline was 1.38 ± 0.38 µV in patients without syncope and 1.42 ± 0.52 µV in patients with syncope (P = .77). On upright tilt, aSKNA was 1.34 ± 0.40 µV in patients who did not have syncope and 1.39 ± 0.43 µV in patients who had syncope (P = .65). In all 14 patients with syncope, there was a surge of SKNA before an initial increase in heart rate followed by bradycardia, hypotension, and syncope. The peak aSKNA immediately (<1 minute) before syncope was significantly higher than baseline aSKNA (2.63 ± 1.22 vs 1.39 ± 0.43 µV; P = .0005). After syncope, patients were immediately placed in the supine position and aSKNA dropped significantly to 1.26 ± 0.43 µV; (P = .0004). The heart rate variability during the TTT shows a significant increase in parasympathetic tone during syncope (low-frequency/high-frequency ratio: 7.15 vs 2.21; P = .04). CONCLUSION: Patients with syncope do not have elevated sympathetic tone at baseline or during the TTT except immediately before syncope when there is a transient surge of SKNA followed by sympathetic withdrawal along with parasympathetic surge.

Effects of anesthetic and sedative agents on sympathetic nerve activity.

BACKGROUND: The effects of sedative and anesthetic agents on sympathetic nerve activity (SNA) are poorly understood. OBJECTIVE: The purpose of this study was to determine the effects of commonly used sedative and anesthetic agents on SNA in ambulatory dogs and humans. METHODS: We implanted radiotransmitters in 6 dogs to record stellate ganglion nerve activity (SGNA), subcutaneous nerve activity (ScNA), and blood pressure (BP). After recovery, we injected dexmedetomidine (3 µg/kg), morphine (0.1 mg/kg), hydromorphone (0.05 mg/kg), and midazolam (0.1 mg/kg) on different days. We also studied 12 human patients (10 male; age 68.0 ± 9.1 years old) undergoing cardioversion for atrial fibrillation with propofol (0.77 ± 0.18 mg/kg) or methohexital (0.65 mg/kg) anesthesia. Skin sympathetic nerve activity (SKNA) and electrocardiogram were recorded during the study. RESULTS: SGNA and ScNA were significantly suppressed immediately after administration of dexmedetomidine (P = .000 and P = .000, respectively), morphine (P = .011 and P = .014, respectively), and hydromorphone (P = .000 and P = .012, respectively), along with decreased BP and heart rate (HR) (P <.001 for each). Midazolam had no significant effect on SGNA and ScNA (P = .248 and P = .149, respectively) but increased HR (P = .015) and decreased BP (P = .004) in ambulatory dogs. In patients undergoing cardioversion, bolus propofol administration significantly suppressed SKNA (from 1.11 ± 0.25 µV to 0.77 ± 0.15 µV; P = .001), and the effects lasted for at least 10 minutes after the final cardioversion shock. Methohexital decreased chest SKNA from 1.59 ± 0.45 µV to 1.22 ± 0.58 µV (P = .000) and arm SKNA from 0.76 ± 0.43 µV to 0.55 ± 0.07 µV (P = .001). The effects lasted for at least 10 minutes after the cardioversion shock. CONCLUSION: Propofol, methohexital, dexmedetomidine, morphine, and hydromorphone suppressed, but midazolam had no significant effects on, SNA.

Significance of a fragmented QRS complex versus a Q wave in patients with coronary artery disease.

BACKGROUND: Q waves on a 12-lead ECG are markers of a prior myocardial infarction (MI). However, they may regress or even disappear over time, and there is no specific ECG sign of a non-Q-wave MI. Fragmented QRS complexes (fQRSs), which include various RSR' patterns, without a typical bundle-branch block are markers of altered ventricular depolarization owing to a prior myocardial scar. We postulated that the presence of an fQRS might improve the ability to detect a prior MI compared with Q waves alone by ECG. METHODS AND RESULTS: A cohort of 479 consecutive patients (mean+/-SD age, 58.2+/-13.2 years; 283 males) who were referred for nuclear stress tests was studied. The fQRS included various morphologies of the QRS (<120 ms), which included an additional R wave (R') or notching in the nadir of the S wave, or >1 R' (fragmentation) in 2 contiguous leads, corresponding to a major coronary artery territory. The Q wave was present in 71 (14.8%) patients, an fQRS was present in 191 (34.9%) patients, and an fQRS and/or a Q wave was present in 203 (42.3%) patients. Sensitivity, specificity, and the negative predictive value for myocardial scar as detected by single photon emission computed tomography analysis were 36.3%, 99.2%, and 70.8%, respectively, for the Q wave alone; 85.6%, 89%, and 92.7%, respectively, for the fQRS; and 91.4%, 89%, and 94.2%, respectively, for the Q wave and/or fQRS. CONCLUSIONS: The fQRS on a 12-lead ECG is a marker of a prior MI, defined by regional perfusion abnormalities, which has a substantially higher sensitivity and negative predictive value compared with the Q wave.

Fragmented left sided QRS in absence of bundle branch block: sign of left ventricular aneurysm.

BACKGROUND: A left ventricular aneurysm (LVA) occurs between 3.5% and 9.4% of all cases of acute myocardial infarction. A fragmented left sided QRS (RSR; pattern or its variant RSr;, rSR;, or rSr;) without evidence of bundle branch block (QRS duration