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An optimal membership function-based fractional order fuzzy proportional integral (Fuzzy-PIλ) power system stabilizer (PSS) is designed to suppress low frequency oscillation (LFO) in a synchronous generator connected to an infinite bus power system. Speed deviation and the change in speed deviation of synchronous generator due to LFO are taken as inputs of the fuzzy controller, and the parameters of a fractional-order PI controller (proportional gain, integral gain, and the fractional term in integral control action) are taken as fuzzy output variables. The range, scaling, and shape of the membership functions of the fuzzy controller are optimized such that it can tune the fractional order proportional integral (PIλ) stabilizer under any disturbance or parametric uncertainty in the synchronous generator. The advantage of the proposed stabilizer is that it can handle a wide range of disturbances and adjust the gains of the control parameters for the system. A nonlinear dynamic acceleration coefficient-based class-topper optimization is applied to optimize the fuzzy settings. The robustness and sensitivity of the proposed optimal Fuzzy-PIλ stabilizer are verified under different scenarios for the synchronous generator and compared with available results.

Persistent left-sided superior vena cava (PLSVC) is rare and is the most common systemic vein anomaly. It is mostly asymptomatic and often an incidental finding. It may pose a challenge in performing intervention through it due to its complex anatomy. We report a case of degenerative symptomatic complete atrioventricular node block in whom PLSVC was found incidentally during permanent pacemaker implantation. We also discussed the technical challenges and how to overcome these difficulties.

Abstract In order to improve the pressure tracking response of an artificial ventilator system, a novel proportional integral derivative (PID) controller is designed in the present work by utilizing an optimal rule-based fuzzy inference system (FIS) with a reshaped class-topper optimization algorithm (RCTO), which is named as (Fuzzy-PID). Firstly, a patient-hose blower-driven artificial ventilator model is considered, and the transfer function model is established. The ventilator is assumed to operate in pressure control mode. Then, a fuzzy-PID control structure is formulated such that the error and change in error between the desired airway pressure and actual airway pressure of the ventilator are set as inputs to the FIS. The gains of the PID controller (proportional gain, derivative gain, and integral gain) are set as outputs of the FIS. A reshaped class topper optimization algorithm (RCTO) is developed to optimize rules of the FIS to establish optimal coordination among the input and output variables of the FIS. Finally, the optimized Fuzzy-PID controller is examined for the ventilator under different scenarios such as parametric uncertainties, external disturbances, sensor noise, and a time-varying breathing pattern. In addition, the stability analysis of the system is carried out using the Nyquist stability method, and the sensitivity of the optimal Fuzzy-PID is examined for different blower parameters. The simulation results showed satisfactory results in terms of peak time, overshoot, and settling time for all cases, which were also compared with existing results. It is observed in the simulation results that the overshoot in the pressure profile is improved by 16% with the proposed optimal rule based fuzzy-PID as compared with randomly selected rules for the system. Settling time and peak time are also improved 60–80% compared to the existing method. The control signal generated by the proposed controller is also improved in magnitude by 80–90% compared to the existing method. With a lower magnitude, the control signal can also avoid actuator saturation problems.

Abstract Computational techniques are widely used to solve complex optimization problems in different fields such as engineering, finance, biology, and so on. In this paper, the Human Conception Optimizer (HCO) is proposed as a novel metaheuristic algorithm to solve any optimization problems. The idea of this algorithm is based on some biological principles of the human conception process, such as the selective nature of cervical gel in the female reproductive system to allow only healthy sperm cells into the cervix, the guidance nature of mucus gel to help sperm track a genital tracking path towards the egg in the Fallopian tube, the asymmetric nature of flagellar movement which allows sperm cells to move in the reproductive system, the sperm hyperactivation process to make them able to fertilize an egg. Thus, the strategies pursued by the sperm in searching for the egg in the Fallopian tube are modeled mathematically. The best sperm which will meet the position of the egg will be the solution of the algorithm. The performance of the proposed HCO algorithm is examined with a set of basic benchmark test functions called IEEE CEC-2005 and IEEE CEC-2020. A comparative study is also performed between the HCO algorithm and other available algorithms. The significance of the results is verified with statistical test methods. To validate the proposed HCO algorithm, two real-world engineering optimization problems are examined. For this purpose, a complex 14 over-current relay based IEEE 8 bus distribution system is considered. With the proposed algorithm, an improvement of 50% to 60% in total relay operating times is observed comparing with some existing results for the same system. Another engineering problem of designing an optimal proportional integral derivative (PID) controller for a blower driven patient hose mechanical ventilator (MV) is examined. A significant improvement in terms of response time, settling time is observed in the MV system by comparing with existing results.

We report a rare case of hypertrophic obstructive cardiomyopathy (HOCM) presenting with mega coronary arteries with obstructive coronary artery disease. Interestingly, the patient had large septals, large diagonals, large obtuse marginal with a large left atrial branch, and a large conus almost mimicking a duplicate right coronary artery. Because of massive left ventricular hypertrophy, to overcome the supply-demand mismatch, coronary arteries may become large or with more arborization in hypertrophic cardiomyopathy but the same is rarely encountered in routine clinical practice. Our case is a rare illustration of the simultaneous presence of mega coronary arteries and critical obstructive coronary artery disease in HOCM in a young male of 38 years of age.

Takayasu arteritis is an arteritis of unknown etiology, resulting in stenosis or dilatation of the aorta and its major branches. .We report a rare case of a giant right common carotid artery aneurysm on the one side in a 29-year-old young male with refractory hypertension with severely stenotic, diffusely diseased, corkscrew appearance of the contralateral carotid artery, which has not been described in the literature so far. Our case is a unique demonstration of nature's paradox in vascular behavior in Takayasu arteritis in the right and left carotid arteries in an index patient; one having a giant aneurysm and the other one being severely stenotic, diffusely diseased with corkscrew appearance.

We describe a rare surface electrocardiogram (EKG) recorded sinus beat initiation of permanent junctional reciprocating tachycardia in a 40-year old female with structurally normal heart presenting with incessant tachycardia over last 48 hours refractory to intravenous amiodarone infusion. Our case is an interesting illustration of sinus beat initiation of PJRT which has been rarely reported.

Coronary anomalies are not commonly encountered in routine clinical practice. This case report is of a 55-year-old female who presented with effort angina, Canadian Cardiovascular Society (CCS) class II, since last six months with shortness of breath. Echocardiography (ECG) revealed the presence of Non ST Elevation Myocardial Infarction (NSTEMI) and the presence of no Regional Wall Motion Abnormality (RWMA), with normal left ventricular systolic function. Right transradial coronary angiogram revealed the presence of separate origin of Left Anterior Descending (LAD) and Left Circumflex (LCX) coronary artery. Although separate origin of LAD and LCX is the most common benign coronary anomaly noted in clinical practice, interestingly both coronary arteries in this case were harboring significant atherosclerotic occlusion and were successfully revascularised with Drug Eluting Stents (DES). Coronary intervention in separate origin of LAD and LCX requires special maneuvers during guide catheter management for percutaneous intervention. Clockwise rotation of the guide catheter to selectively engage the LCX and anticlockwise rotation of the guide catheter to selectively engage the LAD is the key for procedural success during coronary intervention. This case is unique and the first to describe the separate origin of LAD and LCX presenting as NSTEMI with critically obstructive Coronary Artery Disease (CAD) in both of them and age being the only conventional cardiac risk factor behind it.

We present an extremely rare case series of two short dual right coronary arteries (RCAs), causing coronary ischemia without the presence of obstructive coronary artery disease. We describe here the presence of short dual RCA in a 55-year-old nondiabetic, nonhypertensive, and nondyslipidemic male presenting with effort angina New York Heart Association Class II for the last 6 months with strongly positive stress test and another 40-year-old athlete (Central Reserve Police Force Army) without conventional risk factors with effort angina Class II for the last 3 months also with strongly positive stress test. Dual RCA, otherwise known as double RCA, duplicate RCA, or split RCA is extremely rare to encounter in routine clinical practice. The patient had a significant effort angina; in spite of nonatherosclerotic coronaries, small dual RCA terminating much earlier than the intended area of supply was the reason behind coronary ischemia with strongly positive provocative stress test. Short normal dual RCA can be a cause of coronary ischemia although mentioned in the literature; there has been no case report in the world literature till now about short dual nonatherosclerotic RCA causing coronary ischemia. Our case is unique and first to describe short dual RCA terminating much earlier than the intended area of supply can attribute to demand ischemia in the intended area of supply without the presence of obstructive coronary artery disease. We treated the patient with nicorandil to improve myocardial microvascular flow in ischemic region with symptomatic improvement of the patient.

We report a rare case of anomalous origin of right coronary artery (RCA) from the left coronary sinus with a peculiar medusa head pattern of left coronary system in an octogenarian presenting with inferior wall myocardial infarction. Although anomalous origin of RCA from the left coronary sinus is the most common anomaly to be reported, this rare association of extensive arborization of left coronary system appearing like a medusa head is not reported in literature so far. The anomalous RCA harbored critical mid-RCA lesion, but the crux of coronary intervention was that we engaged the anomalous RCA with extra back up guide catheter in place of conventionally used Judkins right guide catheter to engage the anomalous origin and accomplished the coronary intervention with buddy wire technique. Our case is unique and the first to describe the association of medusa head appearance of left coronary circulation in a case of anomalous origin of RCA from the left coronary sinus.

We present a simple novel technique of crossing the calcium spur at right-angle bend in coronary artery by deploying a noninflated balloon over the calcium spur where the tip of the passing stent frequently hits and create difficulty in negotiation of the stent forward. When we deploy a balloon over the calcium spur, the tip of the stent does not hit the edge of the calcium spur and the stent gently slides over the hydrophilic slippery balloon forward with ease. We describe a rare case of intervention in anomalous anterior origin of right coronary artery where we were not able to pass the stent across two 90° bends which were harboring calcium spur. In spite of we adopted buddy wire and triple wire technique to make the bend straight, we were not able to move the stent forward, each time it was hitting at the edge of the calcium spur. We put a 2 mm × 10 mm noninflated semicompliant balloon each time while crossing the right-angle bend with calcium spur which covered the calcium spur and over the balloon we were easily able to slide the stent forward, deployed the stent across the lesion, and achieved distal TIMI III flow. We describe this simple novel technique of “sliding the stent over the balloon technique” to cross the calcium spur remaining at 90°-angle bend causing difficulty in forward negotiation of the stent.

We present the case of a 35-year-old female with small restrictive ventricular septal defect (VSD) presenting with prolonged fever for the last 1 month with vegetation on the right coronary cusp (RCC) of the aortic valve with flail aortic leaflet causing severe aortic regurgitation (AR). Her echocardiography done 1 year back had revealed the presence of small restrictive VSD with a gradient of 80 mm Hg without any prolapse of RCC or presence of AR. She did not have any early diastolic murmur of AR during 3 monthly routine follow-up in the cardiology outpatient department suggestive of previous aortic valve prolapse with AR in the aforesaid period before the infective endocarditis episode. Common sites of the vegetation in small restrictive VSD are right ventricular side of the interventricular septum, undersurface of the tricuspid valve, free wall of the right ventricle, and rarely the pulmonary valve on the low-pressure site of the shunt where the turbulent jet containing the bacteria slows down, and bacteria adhere the underlying endocardium. Normally, vegetation across any turbulent jet does not occur on the high-pressure site due to the reason that bacteria can not adhere to the wall across the turbulent jet in high-pressure zone, which sweeps away all the bacteria from the high-pressure zone to low-pressure zone. Paradoxical finding in our case was that vegetation was noted on the RCC of the aortic valve which was a high-pressure zone, which may be explained by only Bernoulli's phenomenon. Our case illustrates paradoxical vegetation on the RCC of the aortic leaflet in a patient with small restrictive VSD and is also a unique demonstration of left-sided endocarditis in a patient with left-to-right shunt.

We report a rare case of inadvertent distal small diagonal branch perforation noted postleft anterior descending coronary artery revascularization, rescued by Gelfoam closure in a 43-year diabetic male presenting with acute anterior wall ST elevated myocardial infarction. Intermittent balloon inflation for 30 min was not able to seal off the perforation; because of impending late (3–6 h) cardiac tamponade, we closed the perforation with Gelfoam embolization through Caravel microcatheter. Although rarely practiced, this armamentarium should be there in the interventional cardiology laboratory to deal with small vessel perforation (

Aims and objectives: Atrial fibrillation (AF) with preexcitation can be life threatening. Our study evaluated the incidence, clinical features, electrophysiologic characteristics and outcomes of patients presenting with AF and fast ventricular rates associated with an antegrade conducting accessory pathway. Methods: Hospital data of patients who had undergone electrophysiology study and radiofrequency ablation for AF and Wolff-Parkinson-White (WPW) syndrome was retrospectively evaluated over 10 years and prospective data was further collected over 1 year. Out of 2876 patients undergoing electrophysiology study, 320 patients had manifest preexcitation on ECG. Forty one patients who had presented with AF and fast ventricular rates were included in the study. Results: Forty one (12.8%) patients out of 320 patients of WPW syndrome patients presented with AF and fast ventricular rates. Mean age of presentation was 38.5 ± 12.3 yrs. Twenty nine (72.5%) were male. Most common presenting features were palpitations, presyncope and syncope. Twenty eight (71.1%) patients were electrically cardioverted on presentation, of which two patients having narrow complex tachycardia, when given adenosine, developed AF and fast ventricular rates and had to be electrically cardioverted. Intravenous amiodarone converted AF to sinus rhythm in 11 (28.9%) patients. Right postero-septal pathway (33.3%) followed by coronary sinus epicardial pathway (22.9%) were the most commonly located pathways associated with AF. Five (12.2%) patients had multiple pathways. CS diverticulum was seen in 6 (14.7%) patients. Ablation was done during AF in 6 (14.7%) patients. All except one had immediate successful ablation. One patient had a recurrence of preexcitation on follow up and successfully ablated during redo procedure. Conclusion: AF with WPW syndrome is not uncommon. AF is commonly associated with posteriorly located accessory pathways, CS diverticulum and multiple pathways. Radiofrequency ablation has good outcomes. Keywords: Accessory pathway, Atrial fibrillation, Radiofrequency ablation

Supracristal Ventricular Septal Defect (VSD) develops Aortic Regurgitation (AR) with the passage of time due to prolapse of the right coronary cusp. It brings clinical attention in early child hood with an incidental continuous murmur, recurrent respiratory tract infection of failure to thrive. This report is about a rare case of 52-year-old female who presented with increased fatiguability since the last six months. Clinical examination revealed the presence of cardiomegaly with holosystolic-diastolic murmur in Left Upper Sternal Border (LUSB). Echocardiography revealed the presence of supracristal VSD with moderate AR without prolapsing aortic leaflet or dilatation of aortic sinus. In view of presence of moderate AR, the patient was advised to be on Angiotensin Receptor Blocker (ARB) with regular follow-up to monitor the progression of AR. Such a late index presentation of supracristal VSD with moderate AR in fifth decade of life has not been described in literature so far. To conclude, nature retards the natural history with bless in disguise.

We present a rare case of left ventricular noncompaction (LVNC) in a 23-year-old female with recurrent syncope with electrocardiography documentation of apical septal ventricular tachycardia (VT). Abnormal embryological myocardial maturation presenting as LVNC with electrogenic heterogenity across the noncompacted spongiform segments result in recurrent VT and mandates automated intracardiac defibrillator implantation (AICD). These subsets of patients in spite of AICD implantation require life-long broad-spectrum antiarrythmic in the form of amiodarone and beta-blocker to prevent a crisis of VT storm or sudden cardiac death.

Hypertrophic cardiomyopathy (HCM) commonly presents with nonspecific ST-T changes in an electrocardiogram (EKG), and a paucity of literature description exists about index presentation of HCM totally as ST-elevation myocardial infarction (STEMI) in a very young age. The presence of convex ST elevation in surface EKG in HCM patients indicates disease progression, becomes evident in the fifth or sixth decade of life, and warrants further risk stratification for the need of automated intracardiac defibrillator therapy. We present a rare presentation of nonobstructive HCM totally mimicking acute anterior wall STEMI in a very young male in his third decade of life, which has not been described in the literature so far. Because of the presence of typical convex shaped ST elevation with biphasic terminal T wave inversion across anterior precordial leads with ongoing typical angina, the patient was subjected to right transradial coronary angiogram which revealed the presence of normal nonatherosclerotic coronaries.

We present a rare case of Brucella endocarditis in a case of the bicuspid aortic valve in a 51-year-old male presenting with pyrexia of unknown origin for the last 2 months. Infective endocarditis caused by Brucella melitensis is rare to encounter in routine clinical practice. Although we routinely think of Mycoplasma, Legionella, and Coxiella in the cases of blood culture-negative endocarditis, one should think of Brucella melitensis and Scrub typhus as the last arrow to reach the final etiology of infective endocarditis in the subset of diseased aortic or mitral valve. We successfully treated the patient with a combined regimen of rifampicin, gentamicin, and doxycycline therapy; during follow-up, the vegetation of the aortic valve was shrunken and calcified and the patient was asymptomatic.